feat(widgets): next alarm, timer and clock home-screen widgets

Three Glance widgets, mirroring state the app already computes rather
than owning any of their own: the next alarm (AlarmEngine.upcoming()),
the live pill's subject timer (same selection logic, no ticker of its
own — a running countdown is the platform chronometer, exactly like
the ring notification), and the local time growing to world clocks at
larger sizes. WidgetSync collects the same read-only flows the shell
already reads and redraws on change, event-driven (updatePeriodMillis
= 0) — it touches no engine, only re-renders, and covers every write
path including SystemEventReceiver's since the process is already
alive whenever those run.

Tapping a widget reuses the same internal navigation actions the
AlarmClock contract's door already produces; the timer buttons send
the same unexported broadcasts its notification does. A widget is
just another caller of machinery that already exists.

ManifestRulesTest is updated deliberately: three GlanceAppWidgetReceivers
join the exported set, each pinned to exactly the platform-required
APPWIDGET_UPDATE filter and no permission — no new permission is
requested anywhere in this change.

app/src/main/res/layout/widget_chronometer.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Embedded inside a Glance layout via AndroidRemoteViews (widget/TimerWidget.kt):
+    Glance has no chronometer composable, and RemoteViews.setChronometer +
+    setChronometerCountDown is exactly the mechanism TimerNotifications.kt
+    already uses for the same reason — the platform ticks it, not the app.
+-->
+<Chronometer xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/widget_chronometer"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:textColor="?android:attr/textColorPrimary"
+    android:textSize="28sp" />

app/src/main/res/layout/widget_text_clock.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Embedded inside a Glance layout via AndroidRemoteViews (widget/ClockWidget.kt):
+    a self-updating platform clock that honours the device's 12/24-hour
+    setting on its own, with no per-second app code. The timezone is set at
+    render time via RemoteViews.setString(id, "setTimeZone", zoneId).
+-->
+<TextClock xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/widget_text_clock"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:textColor="?android:attr/textColorPrimary"
+    android:textSize="28sp" />

app/src/main/res/values/strings.xml

@@ -341,4 +341,13 @@
     <string name="selfcheck_next_alarm_title">Next alarm, as the system sees it</string>
     <string name="selfcheck_next_alarm_ok">Matches what Clockula scheduled</string>
     <string name="selfcheck_next_alarm_problem">Doesn\'t match what Clockula scheduled — open the app to re-check</string>
+
+    <!-- M10: widgets -->
+    <string name="widget_next_alarm_description">Next alarm</string>
+    <string name="widget_next_alarm_empty">No alarms set</string>
+    <string name="widget_next_alarm_today">Today</string>
+    <string name="widget_timer_description">Timer</string>
+    <string name="widget_timer_new">New timer</string>
+    <string name="widget_timer_expired">Time\'s up</string>
+    <string name="widget_clock_description">Clock</string>
 </resources>

app/src/main/res/xml/widget_clock_info.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
+    android:minWidth="90dp"
+    android:minHeight="40dp"
+    android:minResizeWidth="90dp"
+    android:minResizeHeight="40dp"
+    android:targetCellWidth="2"
+    android:targetCellHeight="2"
+    android:updatePeriodMillis="0"
+    android:resizeMode="horizontal|vertical"
+    android:widgetCategory="home_screen"
+    android:previewImage="@mipmap/ic_launcher"
+    android:description="@string/widget_clock_description" />

app/src/main/res/xml/widget_next_alarm_info.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
+    android:minWidth="110dp"
+    android:minHeight="40dp"
+    android:minResizeWidth="110dp"
+    android:minResizeHeight="40dp"
+    android:targetCellWidth="2"
+    android:targetCellHeight="1"
+    android:updatePeriodMillis="0"
+    android:resizeMode="horizontal|vertical"
+    android:widgetCategory="home_screen"
+    android:previewImage="@mipmap/ic_launcher"
+    android:description="@string/widget_next_alarm_description" />

app/src/main/res/xml/widget_timer_info.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
+    android:minWidth="110dp"
+    android:minHeight="60dp"
+    android:minResizeWidth="110dp"
+    android:minResizeHeight="40dp"
+    android:targetCellWidth="2"
+    android:targetCellHeight="2"
+    android:updatePeriodMillis="0"
+    android:resizeMode="horizontal|vertical"
+    android:widgetCategory="home_screen"
+    android:previewImage="@mipmap/ic_launcher"
+    android:description="@string/widget_timer_description" />