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>

scripts/check_reproducible_release.sh

@@ -34,8 +34,15 @@ else
 fi
 
 # 2. The foojay toolchain resolver must not be present in any Gradle script.
+#    This includes the floret-kit submodule: it's an included build (composite
+#    build via `includeBuild`), so F-Droid evaluates its Gradle scripts too when
+#    building from source — the same offline-scanner bar applies to it.
 gradle_files=("$SETTINGS" "$APP")
 [ -f build.gradle.kts ] && gradle_files+=(build.gradle.kts)
+if [ -d floret-kit ]; then
+  while IFS= read -r f; do gradle_files+=("$f"); done \
+    < <(find floret-kit -name '*.gradle.kts' -not -path '*/build/*')
+fi
 if grep -qi 'foojay' "${gradle_files[@]}"; then
   echo "ERROR: foojay toolchain resolver found in: $(grep -li foojay "${gradle_files[@]}" | tr '\n' ' ')" >&2
   echo "       F-Droid's source scanner rejects org.gradle.toolchains.foojay-resolver" >&2