Merge release/v2.11.0 into feat/agenda-range-limit

Integrate #3/#5/#6 (week-start, time-format, hour-lines) into the agenda
range branch. SettingsViewModel folds all five view prefs into one combine;
WidgetData keeps the range-based window and adds the resolved is24Hour.

Also, in the same Appearance section:
- regroup the rows into four titled-by-spacing groups (theme & colour /
  calendar layout / timeline display / agenda) instead of one long card.
- add an explanatory description line under the title of each agenda-range
  picker (PickerDescription).

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

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

@@ -26,7 +26,7 @@ class SettingsPrefsTest {
         val prefs = SettingsPrefs(newDataStore(tempDir))
         assertThat(prefs.themeMode.first()).isEqualTo(ThemeMode.SYSTEM)
         assertThat(prefs.dynamicColor.first()).isTrue()
-        assertThat(prefs.weekStart.first()).isEqualTo(WeekStartPref.AUTO)
+        assertThat(prefs.weekStart.first()).isEqualTo(WeekStartPref.Auto)
     }
 
     @Test
@@ -44,10 +44,50 @@ class SettingsPrefsTest {
     }
 
     @Test
-    fun `week start round-trips`(@TempDir tempDir: Path) = runTest {
+    fun `week start round-trips any day`(@TempDir tempDir: Path) = runTest {
         val prefs = SettingsPrefs(newDataStore(tempDir))
-        prefs.setWeekStart(WeekStartPref.SUNDAY)
-        assertThat(prefs.weekStart.first()).isEqualTo(WeekStartPref.SUNDAY)
+        prefs.setWeekStart(WeekStartPref.Day(DayOfWeek.SATURDAY))
+        assertThat(prefs.weekStart.first()).isEqualTo(WeekStartPref.Day(DayOfWeek.SATURDAY))
+    }
+
+    @Test
+    fun `legacy MONDAY week-start value migrates to Day`(@TempDir tempDir: Path) = runTest {
+        val store = newDataStore(tempDir)
+        val prefs = SettingsPrefs(store)
+        store.updateData { p ->
+            val m = p.toMutablePreferences()
+            m[SettingsPrefs.WEEK_START_KEY] = "MONDAY"
+            m
+        }
+        assertThat(prefs.weekStart.first()).isEqualTo(WeekStartPref.Day(DayOfWeek.MONDAY))
+    }
+
+    @Test
+    fun `garbage week-start value falls back to Auto`(@TempDir tempDir: Path) = runTest {
+        val store = newDataStore(tempDir)
+        val prefs = SettingsPrefs(store)
+        store.updateData { p ->
+            val m = p.toMutablePreferences()
+            m[SettingsPrefs.WEEK_START_KEY] = "FUNDAY"
+            m
+        }
+        assertThat(prefs.weekStart.first()).isEqualTo(WeekStartPref.Auto)
+    }
+
+    @Test
+    fun `time format defaults to auto and round-trips`(@TempDir tempDir: Path) = runTest {
+        val prefs = SettingsPrefs(newDataStore(tempDir))
+        assertThat(prefs.timeFormat.first()).isEqualTo(TimeFormatPref.AUTO)
+        prefs.setTimeFormat(TimeFormatPref.TWELVE_HOUR)
+        assertThat(prefs.timeFormat.first()).isEqualTo(TimeFormatPref.TWELVE_HOUR)
+    }
+
+    @Test
+    fun `hour lines default off and round-trips`(@TempDir tempDir: Path) = runTest {
+        val prefs = SettingsPrefs(newDataStore(tempDir))
+        assertThat(prefs.showHourLines.first()).isFalse()
+        prefs.setShowHourLines(true)
+        assertThat(prefs.showHourLines.first()).isTrue()
     }
 
     @Test
@@ -265,13 +305,15 @@ class SettingsPrefsTest {
 
     @Test
     fun `explicit week-start prefs resolve regardless of locale`() {
-        assertThat(WeekStartPref.MONDAY.resolveFirstDay(Locale.US)).isEqualTo(DayOfWeek.MONDAY)
-        assertThat(WeekStartPref.SUNDAY.resolveFirstDay(Locale.GERMANY)).isEqualTo(DayOfWeek.SUNDAY)
+        assertThat(WeekStartPref.Day(DayOfWeek.MONDAY).resolveFirstDay(Locale.US))
+            .isEqualTo(DayOfWeek.MONDAY)
+        assertThat(WeekStartPref.Day(DayOfWeek.SATURDAY).resolveFirstDay(Locale.GERMANY))
+            .isEqualTo(DayOfWeek.SATURDAY)
     }
 
     @Test
     fun `auto week start follows the locale convention`() {
-        assertThat(WeekStartPref.AUTO.resolveFirstDay(Locale.GERMANY)).isEqualTo(DayOfWeek.MONDAY)
-        assertThat(WeekStartPref.AUTO.resolveFirstDay(Locale.US)).isEqualTo(DayOfWeek.SUNDAY)
+        assertThat(WeekStartPref.Auto.resolveFirstDay(Locale.GERMANY)).isEqualTo(DayOfWeek.MONDAY)
+        assertThat(WeekStartPref.Auto.resolveFirstDay(Locale.US)).isEqualTo(DayOfWeek.SUNDAY)
     }
 }

app/src/test/java/de/jeanlucmakiola/calendula/data/reminders/ReminderTimeTextTest.kt

@@ -26,10 +26,24 @@ class ReminderTimeTextTest {
             isAllDay = false,
             zone = berlin,
             locale = Locale.GERMANY,
+            is24Hour = true,
         )
         assertThat(text).isEqualTo("09:30 – 10:00")
     }
 
+    @Test
+    fun `12-hour preference renders an am-pm time range`() {
+        val text = reminderTimeText(
+            beginMillis = millisAt(LocalDateTime.of(2026, 6, 11, 14, 0), berlin),
+            endMillis = millisAt(LocalDateTime.of(2026, 6, 11, 15, 0), berlin),
+            isAllDay = false,
+            zone = berlin,
+            locale = Locale.US,
+            is24Hour = false,
+        )
+        assertThat(text).isEqualTo("2:00 PM – 3:00 PM")
+    }
+
     @Test
     fun `timed event crossing midnight includes both dates`() {
         val text = reminderTimeText(
@@ -38,6 +52,7 @@ class ReminderTimeTextTest {
             isAllDay = false,
             zone = berlin,
             locale = Locale.GERMANY,
+            is24Hour = true,
         )
         assertThat(text).contains("11.06.2026")
         assertThat(text).contains("12.06.2026")
@@ -54,6 +69,7 @@ class ReminderTimeTextTest {
             // 02:00 in Berlin — naive local reading would shift the day.
             zone = berlin,
             locale = Locale.GERMANY,
+            is24Hour = true,
         )
         assertThat(text).isEqualTo("11.06.2026")
     }
@@ -66,6 +82,7 @@ class ReminderTimeTextTest {
             isAllDay = true,
             zone = berlin,
             locale = Locale.GERMANY,
+            is24Hour = true,
         )
         assertThat(text).isEqualTo("11.06.2026 – 12.06.2026")
     }
@@ -79,6 +96,7 @@ class ReminderTimeTextTest {
             isAllDay = true,
             zone = berlin,
             locale = Locale.GERMANY,
+            is24Hour = true,
         )
         assertThat(text).isEqualTo("11.06.2026")
     }

app/src/test/java/de/jeanlucmakiola/calendula/ui/common/TimeFormatTest.kt

@@ -0,0 +1,37 @@
+package de.jeanlucmakiola.calendula.ui.common
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.jupiter.api.Test
+import java.util.Locale
+
+class TimeFormatTest {
+
+    @Test
+    fun `24-hour format is zero-padded HH mm`() {
+        assertThat(formatTimeOfDay(9, 5, is24Hour = true, Locale.US)).isEqualTo("09:05")
+        assertThat(formatTimeOfDay(14, 0, is24Hour = true, Locale.US)).isEqualTo("14:00")
+        assertThat(formatTimeOfDay(0, 0, is24Hour = true, Locale.US)).isEqualTo("00:00")
+    }
+
+    @Test
+    fun `12-hour format adds a localised am-pm marker`() {
+        assertThat(formatTimeOfDay(14, 0, is24Hour = false, Locale.US)).isEqualTo("2:00 PM")
+        assertThat(formatTimeOfDay(0, 30, is24Hour = false, Locale.US)).isEqualTo("12:30 AM")
+        assertThat(formatTimeOfDay(12, 0, is24Hour = false, Locale.US)).isEqualTo("12:00 PM")
+    }
+
+    @Test
+    fun `minute-of-day end-of-day renders 24 00 in 24h and midnight in 12h`() {
+        assertThat(formatMinuteOfDay(1_440, is24Hour = true, Locale.US)).isEqualTo("24:00")
+        assertThat(formatMinuteOfDay(1_440, is24Hour = false, Locale.US)).isEqualTo("12:00 AM")
+        assertThat(formatMinuteOfDay(13 * 60 + 15, is24Hour = true, Locale.US)).isEqualTo("13:15")
+    }
+
+    @Test
+    fun `hour label is zero-padded in 24h and compact am-pm in 12h`() {
+        assertThat(formatHourLabel(13, is24Hour = true, Locale.US)).isEqualTo("13")
+        assertThat(formatHourLabel(13, is24Hour = false, Locale.US)).isEqualTo("1 PM")
+        assertThat(formatHourLabel(1, is24Hour = false, Locale.US)).isEqualTo("1 AM")
+        assertThat(formatHourLabel(0, is24Hour = false, Locale.US)).isEqualTo("12 AM")
+    }
+}