feat(event-form): auto-focus the title on a new event, optionally (#10)

Opening the new-event form now puts the cursor in the title field and raises the
keyboard, so the user can type the name straight away instead of tapping the
field first (issue #10). On by default — most events get a title — with a new
"Focus title on new event" switch in Settings → New event form to turn it off.

Only the create form auto-focuses: editing an existing event and opening a
prefilled/imported form never grab focus (guarded by !isEditing && title blank).

- SettingsPrefs: autofocusEventTitle (booleanPreferencesKey), default true.
- Plumbed through SettingsViewModel/UiState (settings switch) and
  EventEditViewModel/UiState (read by the form).
- EventEditScreen: a FocusRequester on the title InlineField, requested once per
  open from a LaunchedEffect when the guard holds.
- Strings (en + de), unit test for the new pref default/round-trip.

Bumps to 2.11.2.

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

app/build.gradle.kts

@@ -28,8 +28,8 @@ android {
         // which builds this version and then creates the matching vX.Y.Z tag +
         // release itself (versionCode is pinned to MAJOR*10000 + MINOR*100 +
         // PATCH from versionName, e.g. 2.7.2 -> 20702). See docs/RELEASING.md.
-        versionCode = 21101
-        versionName = "2.11.1"
+        versionCode = 21102
+        versionName = "2.11.2"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
     }