feat(app): show 25 unread messages per channel in the inbox (#1729)

fluxer_app/src/features/app/components/floating/UnreadChannelsContent.tsx

@@ -3,6 +3,10 @@
 import Accessibility from '@app/features/accessibility/state/Accessibility';
 import {mergeFrozenUnreadOrder} from '@app/features/app/components/floating/UnreadChannelOrder';
 import styles from '@app/features/app/components/floating/UnreadChannelsContent.module.css';
+import {
+	BULK_PREVIEW_CHANNEL_BATCH_SIZE,
+	UNREAD_PREVIEW_MESSAGE_LIMIT,
+} from '@app/features/app/components/floating/UnreadPreviewBudget';
 import previewStyles from '@app/features/app/components/shared/MessagePreview.module.css';
 import {Endpoints} from '@app/features/app/constants/Endpoints';
 import {renderChannelStream} from '@app/features/channel/components/ChannelMessageStream';
@@ -131,8 +135,6 @@ interface ChannelPreviewData {
 
 const INITIAL_VISIBLE_CHANNELS = 10;
 const LOAD_MORE_CHUNK = 10;
-const UNREAD_PREVIEW_MESSAGE_LIMIT = 5;
-const BULK_PREVIEW_CHANNEL_BATCH_SIZE = 10;
 
 interface CacheEntry {
 	cacheKey: string;

fluxer_app/src/features/app/components/floating/UnreadPreviewBudget.test.ts

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import {
+	BULK_PREVIEW_CHANNEL_BATCH_SIZE,
+	UNREAD_PREVIEW_MESSAGE_LIMIT,
+} from '@app/features/app/components/floating/UnreadPreviewBudget';
+import {BulkMessageFetchRequest} from '@fluxer/schema/src/domains/message/MessageRequestSchemas';
+import {describe, expect, it} from 'vitest';
+
+const buildBatch = (limit: number) => ({
+	requests: Array.from({length: BULK_PREVIEW_CHANNEL_BATCH_SIZE}, (_, index) => ({
+		channel_id: String(1000000000000000000n + BigInt(index)),
+		limit,
+	})),
+});
+
+describe('unread preview fetch budget', () => {
+	it('keeps the anchored window inside the bulk fetch schema', () => {
+		expect(() => BulkMessageFetchRequest.parse(buildBatch(UNREAD_PREVIEW_MESSAGE_LIMIT * 2))).not.toThrow();
+	});
+
+	it('keeps the unanchored window inside the bulk fetch schema', () => {
+		expect(() => BulkMessageFetchRequest.parse(buildBatch(UNREAD_PREVIEW_MESSAGE_LIMIT))).not.toThrow();
+	});
+
+	it('rejects a batch one channel wider than the client sends', () => {
+		const oversized = buildBatch(UNREAD_PREVIEW_MESSAGE_LIMIT * 2);
+		oversized.requests.push({channel_id: '1000000000000000099', limit: UNREAD_PREVIEW_MESSAGE_LIMIT * 2});
+		expect(() => BulkMessageFetchRequest.parse(oversized)).toThrow();
+	});
+});

fluxer_app/src/features/app/components/floating/UnreadPreviewBudget.ts

@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+export const UNREAD_PREVIEW_MESSAGE_LIMIT = 25;
+export const BULK_PREVIEW_CHANNEL_BATCH_SIZE = 5;