Port field moves from the menu, SEL with Select, and moving Pokémon in Bill's PC

Field moves chosen in the party menu run their original checks and the
ROM's from-menu scripts (Cut, Surf, Strength, Flash, Whirlpool, Waterfall,
Sweet Scent), and Softboiled and Milk Drink share HP. SEL registers a key
item that Select then uses, replacing the Key Items shortcut, and Bill's
PC moves Pokémon between the party and every box.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/PLAN.md

@@ -130,7 +130,7 @@ The numbered sections below keep their full scope. Each one opens with a checkli
 - Capture with a full party runs `SendMonIntoBox`: the Pokémon goes first in the current box, with restored PP and `SetBoxMonCaughtData`, can be nicknamed and shows `BallSentToPCText`. If the box is already full the ball is not used (`Ball_BoxIsFullMessage`). A catch that fills the box sets `BATTLERESULT_BOX_FULL`; `reloadmapafterbattle` then queues Bill's call (`Script_SpecialBillCall`) as a memory script that runs at the next `PlayerEvents` and is not saved, as in the original.
 - `VAR_BOXSPACE` reads the current box.
 - Save format 3 gained `storage` (boxes, the current box and box names; a null name is the ROM default) and `pcItems`, migrated by absence to empty storage.
-- Not ported: MOVE PKMN W/O MAIL (a notice returns to the menu; the stats screen is now ported), printing, a `givepoke` with a full party (refused; no open map reaches it) and the tutorial with a full party and box (the original repeats the unusable ball). Changing boxes does not show the save messages; the native session saves continuously.
+- Not ported: printing (MOVE PKMN W/O MAIL and the stats screen are ported since), a `givepoke` with a full party (refused; no open map reaches it) and the tutorial with a full party and box (the original repeats the unusable ball). Changing boxes does not show the save messages; the native session saves continuously.
 - Next: the introduction's naming and clock screens, player switching and other items in battle, then party and bag menus.
 
 ## Implemented: the introduction's naming and clock screens
@@ -169,7 +169,7 @@ The numbered sections below keep their full scope. Each one opens with a checkli
 - PACK: the Items, Balls, Key and TM pockets (left and right change pockets; there are no TMs or HMs yet), and each item's submenu chosen by its permissions and field menu (`USE`, `GIVE`, `TOSS`, `SEL`, `QUIT`). TOSS asks how many and confirms. USE follows `UseItem`: Oak's warning without a field use, "You don't have a POKéMON!" for party items without one, and `_DoItemEffect` by the item's `ItemEffects` address: Potions and the other `HealingHPAmounts` items, status healers, Full Restore, Revive and Max Revive, the bitter Energypowder, Energy Root, Heal Powder and Revival Herb, Ethers, Elixers, the MysteryBerry and PP Up. The Bicycle closes the menu and runs `Script_GetOnBike` or `Script_GetOffBike` outdoors; elsewhere Oak objects, because `wFieldMoveSucceeded` shares `wItemEffectSucceeded`'s byte.
 - PP Up keeps a quirk: `wUsePPUp` shares `wTempPP`'s byte, so `ComputeMaxPP` adds one step (a fifth of the base PP, at most 7) to the current PP as well as the maximum. Sketch and moves with three PP Ups are "maxed out".
 - The menu runs on a script draft, like the PC. Changes commit when it closes; a save made while it is open keeps the state from before it. The start menu cursor, the party menu cursor and the last pocket stay in memory between openings and are cleared after a battle, as `CleanUpBattleRAM` does. The party cursor reaches the next battle's `ChangeHappiness`.
-- Select keeps opening the Key Items shortcut, standing in for a registered item. Not ported: field moves from the menu, MAIL, SEL (registering items), moving a Pokémon's moves to another party member with left and right, item reordering with Select and the remaining field items such as Repel and Escape Rope (each gives a notice and changes nothing). Rare Candy, evolution stones and vitamins run since the evolution section below.
+- Not ported: MAIL, moving a Pokémon's moves to another party member with left and right, item reordering with Select and the remaining field items such as Repel and Escape Rope (each gives a notice and changes nothing). Rare Candy, evolution stones and vitamins run since the evolution section below; field moves, SEL and Select since the section after it.
 
 ## Implemented: evolution
 
@@ -180,11 +180,21 @@ The numbered sections below keep their full scope. Each one opens with a checkli
 - PACK: Rare Candy (`RareCandyEffect`: one level at the level's minimum experience; the HP gains the maximum HP's increase even for a fainted Pokémon; the caught-location happiness bonus; "grew to level", the stat box, new moves and a possible evolution), evolution stones (`EvoStoneEffect`: a forced `EvolvePokemon`; the party menu shows ABLE or NOT ABLE with the original's ten-byte, three-byte-step check; an Everstone or no matching evolution has no effect) and vitamins (`VitaminEffect`: ten more in the stat experience's high byte, up to 100, stats recomputed without changing the current HP, happiness).
 - Not presented: the evolution music, cries and the palette changes. Trade evolutions need Link.
 
+## Implemented: field moves from the menu, SEL and moving Pokémon
+
+- Field moves in the Pokémon submenu run their menu functions: the world checks the badge (`CheckBadge`: "Sorry! A new BADGE is required."), the facing tile, water or object, then the menu closes and the ROM's `…FromMenu` script runs for the chosen Pokémon (no "Want to …?" question): Cut (`CheckMapForSomethingToCut`), Surf (including "already surfing" and forced cycling), Strength, Flash (a `PALETTE_DARK` map or the Aerodactyl chamber; `BlindingFlash` sets the Flash flag), Whirlpool and Waterfall. Failures print the ROM's messages and return to the party menu.
+- Sweet Scent runs `SweetScentFromMenu`: where wild Pokémon can appear and the map has a rate, `ChooseWildEncounter` picks one without the rate roll and a battle starts; elsewhere "Looks like there's nothing here…".
+- Softboiled and Milk Drink give a fifth of the user's maximum HP to another Pokémon that has not fainted and is not at full HP; the user needs more than that fifth.
+- Fly (outdoors with the Storm Badge), Dig (in caves), Teleport (outdoors with a spawn point), Headbutt (facing a tree) and Rock Smash (facing a rock) run their checks and messages, then give a notice: the Fly map, dungeon and spawn warps, tree encounters and rock encounters are not ported.
+- SEL registers an item that `CANT_SELECT` allows (in practice key items) in `wWhichRegisteredItem` and `wRegisteredItem`, which saves keep. Select runs `SelectMenu`: `CheckRegisteredItem` (a slot that no longer holds the item clears the registration; a registered ball is never found, as in the original) and `UseRegisteredItem` by field menu. The Bicycle uses `Script_GetOnBike_Register` and `Script_GetOffBike_Register`, without a message; elsewhere Oak objects. Without a registration Select explains SEL. This replaces the earlier Key Items shortcut.
+- Bill's PC's MOVE PKMN W/O MAIL: refused while a party Pokémon holds MAIL, then "Each time you move a POKéMON, data will be saved. OK?". Choose the party or a box, a Pokémon (MOVE, STATS, CANCEL), then a box and the position to insert before. The party keeps its last Pokémon and its last healthy one, a different full box or party has "no room", a Pokémon moved down its own list lands one place earlier (`.CheckTrivialMove`), a boxed Pokémon joining the party gets its stats with full HP and no status (`CalcBufferMonStats`), and one entering a box gets its PP restored. The original's left/right box switching is presented as a list of boxes; after "no room" the box is chosen again rather than the position.
+- Save format 3 gained `registeredItem`, migrated by absence to none.
+
 ## Native battles: current state
 
 The battle core, ROM tables, encounter hooks, battle UI and whiteout hooks are present. Unit tests cover wins, escape, loss, experience, move learning and capture; reference tests compare damage, type effectiveness, stat calculation and experience curves. Browser tests drive a test-only wild encounter through the real UI: victory with level-up and move learning, escape, whiteout, catching with a nickname, keyboard and on-screen D-pad menu navigation, mid-battle backup restore, rollback of unsupported effects, switching through the party menu and a Potion from the Items pocket. Real Route 29 encounters now use the ROM's encounter tables. Only the special Kurt and Park balls remain unported among battle items.
 
-This is still not a complete new game. The Pokégear, Pokédex and trainer card screens, story progression beyond Route 30 and Mr. Pokémon's house, and audio remain unfinished. The start menu opens the party menu and the pack, and the Key Items shortcut supports the Bicycle; the PCs store Pokémon, items and decorations. Surfing and terrain animation now have native implementations; later maps remain gated. Save slots, a Johto/Kanto atlas, Pokédex records, online Link, friends and real-world steps come later.
+This is still not a complete new game. The Pokégear, Pokédex and trainer card screens, story progression beyond Route 30 and Mr. Pokémon's house, and audio remain unfinished. The start menu opens the party menu and the pack, and Select uses the registered item, such as the Bicycle; the PCs store Pokémon, items and decorations. Surfing and terrain animation now have native implementations; later maps remain gated. Save slots, a Johto/Kanto atlas, Pokédex records, online Link, friends and real-world steps come later.
 
 ## 1. Complete the overworld foundation
 
@@ -196,7 +206,7 @@ This is still not a complete new game. The Pokégear, Pokédex and trainer card
 - [x] Connected transitions for every enabled map (New Bark Town to Route 30)
 - [x] Dynamic warps, elevators, ice, currents and forced movement
 - [x] Native Surf, Cut and Strength interactions, cycling rules and boulder holes
-- [x] Bicycle access from the Key Items menu with keyboard and touch controls
+- [x] Bicycle access from the pack or a registered Select, with keyboard and touch controls
 - [x] Tile changes (`changeblock`, `changemapblocks`) with rollback and minimap refresh
 - [x] Room decorations, ownership, selection, removal, save validation and migration
 - [x] Additional NPC movement types, variable sprites, Pokémon icons and movement-command decoding
@@ -230,8 +240,8 @@ pixel-perfect screenshots or full Celebi story support.
 
 The bedroom PC selects and puts away owned decorations, including left/right
 doll placement. Room blocks, sprites and descriptions reflect saved choices.
-The Town Map poster opens the native ROM-backed map. Select opens Key Items
-(Start now opens the start menu); using the Bicycle follows the native
+The Town Map poster opens the native ROM-backed map. Start opens the start
+menu and Select the registered item; using the Bicycle follows the native
 outdoor/indoor rules. Browser
 checks cover both controls and decoration flows in Chromium and WebKit.
 Full item/Pokémon PC storage and the other bag pockets belong to later work.
@@ -262,7 +272,7 @@ Introduce native player, party, Pokémon, inventory, money and quest models. Rea
 
 Expand script calls, choices, scene state, inventory commands and native special handlers. Translate routines reached through assembly calls into explicit native services; never fall back to emulator execution in the shipping game.
 
-Meeting Mom, Elm's introduction, the starter, the aide's Potion, Route 29, Cherrygrove, Route 30's trainers, Mr. Pokémon's house, the Cherrygrove rival battle, the return to Elm, capture, the catching tutorial, the PC, the introduction's naming and clock screens, and switching and healing items in battle run now. The opening milestone is complete within the recorded acceptance boundaries. The start menu, party menu and pack now run outside battle, and Pokémon evolve. Next: MOVE PKMN W/O MAIL, SEL and field moves from the menu, then the Pokégear.
+Meeting Mom, Elm's introduction, the starter, the aide's Potion, Route 29, Cherrygrove, Route 30's trainers, Mr. Pokémon's house, the Cherrygrove rival battle, the return to Elm, capture, the catching tutorial, the PC, the introduction's naming and clock screens, and switching and healing items in battle run now. The opening milestone is complete within the recorded acceptance boundaries. The start menu, party menu and pack now run outside battle, and Pokémon evolve. Field moves from the menu, SEL/Select and MOVE PKMN W/O MAIL run too. Next: the Pokégear, then the trainer card and options.
 
 Complete and validate the native battle engine: deterministic randomness, stats, move selection, accuracy/critical checks, damage, status, turn order, switching, fainting, experience, capture and rewards. Compare controlled seeds and states with the original, including integer rounding and overflow behavior.
 
@@ -294,7 +304,8 @@ Acceptance: main-game/postgame playthroughs, representative optional content, ba
 - [x] Save, backup export and import for the single native save
 - [x] Touch battle commands, move list, PKMN party menu, PACK (Items and Balls pockets) and naming fields
 - [x] Start menu, party menu and pack outside battle (switching, moves, held items, healing and PP items, tossing, the Bicycle)
-- [ ] Pokégear, Pokédex, trainer card and options screens; MOVE PKMN W/O MAIL
+- [x] Bill's PC: MOVE PKMN W/O MAIL between the party and every box
+- [ ] Pokégear, Pokédex, trainer card and options screens
 - [ ] Scalable text, configurable controls and fuller accessibility
 - [ ] Save slots with migration, atomic writes and import previews
 - [ ] Installable web app with offline app shell, safe updates and quota handling