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>

docs/fdroid-official/de.jeanlucmakiola.calendula.yml

@@ -43,11 +43,21 @@ Builds:
     versionCode: 20705
     commit: v2.7.5
     subdir: app
+    submodules: true
     gradle:
       - yes
     # No NDK / no flavors. The release buildType applies a signingConfig only
     # when key.properties exists; on the buildserver it does not, so this
     # produces the unsigned APK F-Droid compares against our binary.
+    #
+    # submodules: true — REQUIRED from v2.11.0 onward, where the build pulls
+    # shared code from the `floret-kit` git submodule via a Gradle composite
+    # build (`includeBuild("floret-kit")`). Without it F-Droid checks out an
+    # empty floret-kit/ and the from-source build fails, stalling publishing.
+    # Inert for v2.7.5 (no submodule yet); kept here so AutoUpdateMode copies it
+    # onto every auto-generated future build entry. The kit is plain-Kotlin and
+    # carries no foojay toolchain resolver, so it clears the same reproducibility
+    # bar (enforced by scripts/check_reproducible_release.sh).
 
 # SHA-256 of our app signing certificate (public; embedded in every published
 # APK). Locks F-Droid to publish only binaries signed with our key.