feat(05-02): printer detail page with export buttons and command preview

- Update printer_detail() to pass install_cmd, uninstall_cmd, has_driver, has_icon to template
- Rewrite printer_detail.html with Intune Commands, Export, and Icon sections
- Show command strings with Alpine.js copy-to-clipboard buttons (install-cmd, uninstall-cmd)
- Show NinjaRMM ZIP and .intunewin download links when driver assigned
- Add HTMX icon upload form with #icon-status swap target
- Remove disabled placeholder Regenerate Package button
- Add TestCommandPreview class (4 tests) to test_packages.py
- All 94 tests pass

imptune/api/pages.py

@@ -76,7 +76,7 @@ def printers_page(request: Request):
 
 @router.get("/printers/{printer_id}", response_class=HTMLResponse)
 def printer_detail(request: Request, printer_id: int):
-    from imptune.db.models import Client, Driver, Printer
+    from imptune.db.models import Client, Driver, Icon, Printer
 
     printer = (
         Printer.select(Printer, Client, Driver)
@@ -96,10 +96,23 @@ def printer_detail(request: Request, printer_id: int):
     if printer.driver_id and printer.driver.driver_desc:
         driver_names = json.loads(printer.driver.driver_desc)
 
+    has_driver = printer.driver_id is not None and bool(driver_names)
+    icon = Icon.get_or_none(Icon.printer == printer_id)
+
+    install_cmd = "powershell.exe -ExecutionPolicy Bypass -File install.ps1"
+    uninstall_cmd = "powershell.exe -ExecutionPolicy Bypass -File uninstall.ps1"
+
     return templates.TemplateResponse(
         request=request,
         name="printer_detail.html",
-        context={"printer": printer, "driver_names": driver_names},
+        context={
+            "printer": printer,
+            "driver_names": driver_names,
+            "has_driver": has_driver,
+            "has_icon": icon is not None,
+            "install_cmd": install_cmd,
+            "uninstall_cmd": uninstall_cmd,
+        },
     )