Refactor notifications to Kotlin & paging (#4026)

This refactors the NotificationsFragment and related classes to Kotlin &
paging.
While trying to preserve as much of the original behavior as possible,
this adds the following improvements as well:
- The "show notifications filter" preference was added again
- The "load more" button now has a background ripple effect when clicked
- The "legal" report category of Mastodon 4.2 is now supported in report
notifications
- Unknown notifications now display "unknown notification type" instead
of an empty line

Other code quality improvements:
- All views from xml layouts are now referenced via ViewBindings
- the classes responsible for showing system notifications were moved to
a new package `systemnotifications` while the classes from this
refactoring are in `notifications`
- the id of the local Tusky account is now called `tuskyAccountId` in
all places I could find

closes https://github.com/tuskyapp/Tusky/issues/3429

---------

Co-authored-by: Zongle Wang <wangzongler@gmail.com>

app/src/main/java/com/keylesspalace/tusky/db/DatabaseCleaner.kt

@@ -0,0 +1,66 @@
+/* Copyright 2024 Tusky Contributors
+ *
+ * This file is a part of Tusky.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Tusky; if not,
+ * see <http://www.gnu.org/licenses>. */
+
+package com.keylesspalace.tusky.db
+
+import androidx.room.withTransaction
+import com.keylesspalace.tusky.db.entity.HomeTimelineEntity
+import com.keylesspalace.tusky.db.entity.NotificationEntity
+import com.keylesspalace.tusky.db.entity.NotificationReportEntity
+import com.keylesspalace.tusky.db.entity.TimelineAccountEntity
+import com.keylesspalace.tusky.db.entity.TimelineStatusEntity
+import javax.inject.Inject
+
+class DatabaseCleaner @Inject constructor(
+    private val db: AppDatabase
+) {
+    /**
+     * Cleans the [HomeTimelineEntity], [TimelineStatusEntity], [TimelineAccountEntity], [NotificationEntity] and [NotificationReportEntity] tables from old entries.
+     * Should be regularly run to prevent the database from growing too big.
+     * @param tuskyAccountId id of the account for which to clean tables
+     * @param timelineLimit how many timeline items to keep
+     * @param notificationLimit how many notifications to keep
+     */
+    suspend fun cleanupOldData(
+        tuskyAccountId: Long,
+        timelineLimit: Int,
+        notificationLimit: Int
+    ) {
+        db.withTransaction {
+            // the order here is important - foreign key constraints must not be violated
+            db.notificationsDao().cleanupNotifications(tuskyAccountId, notificationLimit)
+            db.notificationsDao().cleanupReports(tuskyAccountId)
+            db.timelineDao().cleanupHomeTimeline(tuskyAccountId, timelineLimit)
+            db.timelineStatusDao().cleanupStatuses(tuskyAccountId)
+            db.timelineAccountDao().cleanupAccounts(tuskyAccountId)
+        }
+    }
+
+    /**
+     * Deletes everything from the [HomeTimelineEntity], [TimelineStatusEntity], [TimelineAccountEntity], [NotificationEntity] and [NotificationReportEntity] tables for one user.
+     * Intended to be used when a user logs out.
+     * @param tuskyAccountId id of the account for which to clean tables
+     */
+    suspend fun cleanupEverything(tuskyAccountId: Long) {
+        db.withTransaction {
+            // the order here is important - foreign key constraints must not be violated
+            db.notificationsDao().removeAllNotifications(tuskyAccountId)
+            db.notificationsDao().removeAllReports(tuskyAccountId)
+            db.timelineDao().removeAllHomeTimelineItems(tuskyAccountId)
+            db.timelineStatusDao().removeAllStatuses(tuskyAccountId)
+            db.timelineAccountDao().removeAllAccounts(tuskyAccountId)
+        }
+    }
+}