chore: draw shared code from floret-kit (fresh re-migration onto current main)

Supersedes the stale chore/floret-kit-core-time branch: re-applies the
floret-kit migration on top of current main (122 commits ahead of the old
branch's base), pinning the kit at the multi-value-reminders + pinned-picker HEAD.

- Submodule + composite build (includeBuild), 6 module deps, CI submodules:
  recursive, reproducible-release scan extended to the kit, F-Droid recipe.
- Deletes the inline copies now owned by the kit (GroupedList, Picker scaffolds,
  InlineTextField, OptionCard, DialogControls, CrashReporter + dialog/submit,
  OnboardingScaffold, AppLanguage, TimeBridge, ReorderableColumn, DebugRibbon)
  and redraws them from components/identity/core-crash/core-locale/core-time.
- Reminder overrides drawn from core-reminders (multi-value ReminderOverride +
  codec); Calendula keeps its app-specific bits (all-day resolution, labels,
  presets, the multi-select ReminderDefaultPicker, its own CrashReportActivity).
- Theme draws FloretExpressiveTheme while keeping the user-typography param.

Build pending (deferred): run ./gradlew :app:compileDebugKotlin with ANDROID_HOME
(or floret-kit/local.properties) set.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/ci.yaml

@@ -29,6 +29,7 @@ jobs:
         with:
           # Full history so the base..HEAD diff below has a merge-base.
           fetch-depth: 0
+          submodules: recursive
 
       # Cheap, always-on guard: the release build must stay reproducible for the
       # official F-Droid repo (no AGP VCS-info embedding). Runs regardless of