fix: key courseTableProvider by semester ID to prevent unnecessary recreations

Author: rileychh

lib/repositories/course_repository.dart

@@ -248,20 +248,18 @@ class CourseRepository {
   /// DB is updated.
   ///
   /// Use [getCourseOffering] for related data (teachers, classrooms, schedules).
-  Stream<CourseTableData> watchCourseTable({
-    required Semester semester,
-  }) async* {
+  Stream<CourseTableData> watchCourseTable({required int semesterId}) async* {
     const ttl = Duration(days: 3);
 
     final query = _database.select(_database.courseTableSlots)
-      ..where((s) => s.semester.equals(semester.id));
+      ..where((s) => s.semester.equals(semesterId));
 
     await for (final rows in query.watch()) {
       final data = _buildCourseTableData(rows);
 
       if (data.isEmpty) {
         try {
-          await refreshCourseTable(semester: semester);
+          await refreshCourseTable(semesterId: semesterId);
         } catch (_) {
           // Absorb: yield empty below so UI exits loading state
         }
@@ -271,14 +269,15 @@ class CourseRepository {
 
       final semesterRow = await (_database.select(
         _database.semesters,
-      )..where((s) => s.id.equals(semester.id))).getSingle();
+      )..where((s) => s.id.equals(semesterId))).getSingle();
       final age = switch (semesterRow.courseTableFetchedAt) {
         final t? => DateTime.now().difference(t),
         null => ttl,
       };
+
       if (age >= ttl) {
         try {
-          await refreshCourseTable(semester: semester);
+          await refreshCourseTable(semesterId: semesterId);
         } catch (_) {
           // Absorb: stale data is shown via stream
         }
@@ -290,10 +289,11 @@ class CourseRepository {
   ///
   /// The [watchCourseTable] stream automatically emits the updated value.
   /// Network errors propagate to the caller.
-  Future<void> refreshCourseTable({
-    required Semester semester,
-  }) async {
+  Future<void> refreshCourseTable({required int semesterId}) async {
     final user = await _database.select(_database.users).getSingle();
+    final semester = await (_database.select(
+      _database.semesters,
+    )..where((s) => s.id.equals(semesterId))).getSingle();
 
     final dtos = await _authRepository.withAuth(
       () => _courseService.getCourseTable(

lib/screens/main/course_table/course_table_providers.dart

@@ -16,12 +16,12 @@ final courseTableSemestersProvider = StreamProvider.autoDispose<List<Semester>>(
 ///
 /// Watches the DB directly — automatically updates when course table data
 /// changes. Background-refreshes stale data automatically.
+///
+/// Keyed by [Semester.id] (not the full object) so that timestamp updates
+/// on the semester row don't recreate the provider.
 final courseTableProvider = StreamProvider.autoDispose
-    .family<CourseTableData, Semester>((
-      ref,
-      semester,
-    ) {
+    .family<CourseTableData, int>((ref, semesterId) {
       return ref
           .watch(courseRepositoryProvider)
-          .watchCourseTable(semester: semester);
+          .watchCourseTable(semesterId: semesterId);
     });

lib/screens/main/course_table/course_table_screen.dart

@@ -24,10 +24,10 @@ class CourseTableScreen extends ConsumerWidget {
     Semester semester,
   ) async {
     final courseRepository = ref.read(courseRepositoryProvider);
-    await Future.wait([
+    await [
       courseRepository.refreshSemesters(),
-      courseRepository.refreshCourseTable(semester: semester),
-    ]);
+      courseRepository.refreshCourseTable(semesterId: semester.id),
+    ].wait;
   }
 
   void _showDemoTap(BuildContext context) {
@@ -164,7 +164,7 @@ class CourseTableScreen extends ConsumerWidget {
                       Consumer(
                         builder: (context, tabRef, child) {
                           final courseTableAsync = tabRef.watch(
-                            courseTableProvider(semester),
+                            courseTableProvider(semester.id),
                           );
 
                           return switch (courseTableAsync) {