chore: complete v1.3 milestone — Backend Expansion

Archives v1.3 milestone (Phase 13: 18 rclone backends), updates PROJECT.md
with all 30 validated requirements, reorganizes ROADMAP.md with all 4 milestones
in collapsed details blocks, adds v1.2 and v1.3 retrospective entries.

Also commits minor CSS token fixes in src/ (text-on-surface-container class
alignment) that were uncommitted from phase 13 execution.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.planning/STATE.md

@@ -2,10 +2,10 @@
 gsd_state_version: 1.0
 milestone: v1.3
 milestone_name: Backend Expansion
-status: verifying
-stopped_at: Completed 13-04-PLAN.md
-last_updated: "2026-04-01T15:33:04.002Z"
-last_activity: 2026-04-01 — Phase 13 plan 04 complete, visual verification approved (REMOTE-05 satisfied)
+status: milestone_complete
+stopped_at: v1.3 milestone archived and closed
+last_updated: "2026-04-16T15:00:00.000Z"
+last_activity: 2026-04-16 — v1.3 Backend Expansion milestone complete, archived, git tagged
 progress:
   total_phases: 6
   completed_phases: 6
@@ -21,16 +21,15 @@ progress:
 See: .planning/PROJECT.md (updated 2026-03-31)
 
 **Core value:** An IT pro can go from zero to a deployable rclone setup in minutes — without needing to know rclone's config syntax or PowerShell deployment conventions.
-**Current focus:** v1.2 — UI Polish & Clarity (Phase 11: Polish & Responsiveness in progress, plan 11-01 complete)
+**Current focus:** Planning next milestone (v1.4)
 
 ## Current Position
 
-Phase: 13 of 13 (Add Remaining RClone Remotes) — Complete
-Plan: 13-04 (complete — all 4 plans complete)
-Status: Phase 13 complete — all 18 backends fully integrated end-to-end, user visual verification approved
-Last activity: 2026-04-01 — Phase 13 plan 04 complete, visual verification approved (REMOTE-05 satisfied)
+Milestone v1.3 complete and archived. Ready for next milestone planning.
+Status: 4 milestones shipped (v1.0 → v1.3), 13 phases, 40 plans — all complete
+Last activity: 2026-04-16 — v1.3 Backend Expansion milestone archived and git tagged
 
-Progress: [██████████] 100% (v1.3)
+Progress: [██████████] 100% (v1.3 — milestone complete)
 
 ## Accumulated Context
 
@@ -99,6 +98,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-04-01T15:27:20.814Z
-Stopped at: Completed 13-04-PLAN.md
+Last session: 2026-04-16
+Stopped at: v1.3 milestone complete — MILESTONES.md, PROJECT.md, ROADMAP.md, RETROSPECTIVE.md updated; git tagged v1.3
 Resume file: None