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/src/test/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefsTest.kt

@@ -90,6 +90,14 @@ class SettingsPrefsTest {
         assertThat(prefs.showHourLines.first()).isTrue()
     }
 
+    @Test
+    fun `autofocus event title defaults on and round-trips`(@TempDir tempDir: Path) = runTest {
+        val prefs = SettingsPrefs(newDataStore(tempDir))
+        assertThat(prefs.autofocusEventTitle.first()).isTrue()
+        prefs.setAutofocusEventTitle(false)
+        assertThat(prefs.autofocusEventTitle.first()).isFalse()
+    }
+
     @Test
     fun `agenda ranges default to month and round-trip independently`(@TempDir tempDir: Path) = runTest {
         val prefs = SettingsPrefs(newDataStore(tempDir))