test(channelserver): add handler coverage tests for misc, cafe, festa, event

Add four new test files covering previously-untested handler functions
to raise total coverage from 57.7% to 60.0%:

- handlers_misc_coverage_test.go: minidata, trend weapons, etc points,
  equip skin history
- handlers_cafe_coverage_test.go: cafe duration bonuses, daily cafe,
  cafe duration
- handlers_festa_coverage_test.go: mezfes data, festa voting, entry,
  charge, prizes, state queries, member enumeration
- handlers_event_coverage_test.go: weekly schedule, login boost,
  scenario data, friends/blacklist operations

Also make mockCharacterRepo.ReadEtcPoints configurable to support
etc points handler tests.

server/channelserver/repo_mocks_test.go

@@ -121,6 +121,12 @@ type mockCharacterRepo struct {
 	loadSaveDataNew  bool
 	loadSaveDataName string
 	loadSaveDataErr  error
+
+	// ReadEtcPoints mock fields
+	etcBonusQuests uint32
+	etcDailyQuests uint32
+	etcPromoPoints uint32
+	etcPointsErr   error
 }
 
 func newMockCharacterRepo() *mockCharacterRepo {
@@ -205,7 +211,7 @@ func (m *mockCharacterRepo) SetDeleted(_ uint32) error
 func (m *mockCharacterRepo) UpdateDailyCafe(_ uint32, _ time.Time, _, _ uint32) error { return nil }
 func (m *mockCharacterRepo) ResetDailyQuests(_ uint32) error                          { return nil }
 func (m *mockCharacterRepo) ReadEtcPoints(_ uint32) (uint32, uint32, uint32, error) {
-	return 0, 0, 0, nil
+	return m.etcBonusQuests, m.etcDailyQuests, m.etcPromoPoints, m.etcPointsErr
 }
 func (m *mockCharacterRepo) ResetCafeTime(_ uint32, _ time.Time) error { return nil }
 func (m *mockCharacterRepo) UpdateGuildPostChecked(_ uint32) error     { return nil }