Fix two flaky tests (wiki-page id collision, legacy decrypt)

src/__tests__/database.spec.ts

@@ -1,4 +1,4 @@
-import { beforeEach, describe, expect, it } from 'vitest'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import initSqlJs from 'sql.js'
 import { AppDatabase, type Book, type Chapter, type ImageAsset } from '@/lib/database'
 
@@ -49,9 +49,17 @@ function chapter(overrides: Partial<Chapter> = {}): Chapter {
 let db: AppDatabase
 
 beforeEach(async () => {
+  // Row ids are built from Date.now(); make it strictly increasing so records
+  // created within the same millisecond (e.g. two wiki pages) get unique ids.
+  let tick = 1_800_000_000_000
+  vi.spyOn(Date, 'now').mockImplementation(() => (tick += 1))
   db = await makeDb()
 })
 
+afterEach(() => {
+  vi.restoreAllMocks()
+})
+
 describe('books', () => {
   it('saves and reads books back', async () => {
     await db.saveBook(book())

src/__tests__/encryption.spec.ts

@@ -56,11 +56,17 @@ describe('Encryption (legacy CryptoJS fallback)', () => {
     expect(decode(decrypted)).toBe('legacy backup text')
   })
 
-  it('throws when a legacy backup is decrypted with the wrong password', async () => {
+  it('never returns the original plaintext for a legacy backup with the wrong password', async () => {
     const legacy = CryptoJS.AES.encrypt('legacy backup text', 'pw').toString()
-    // A wrong password yields garbage bytes; CryptoJS may surface this either as
-    // the source's own "wrong password" error or as an internal "Malformed UTF-8
-    // data" throw, depending on the bytes. Either way it must reject.
-    await expect(Encryption.decrypt(legacy, 'nope')).rejects.toThrow()
+    // A wrong password usually throws (bad padding / malformed UTF-8), but can
+    // occasionally decode to non-empty garbage. The deterministic invariant is
+    // that it must never yield the original plaintext.
+    let recovered: string | null = null
+    try {
+      recovered = decode(await Encryption.decrypt(legacy, 'nope'))
+    } catch {
+      // Throwing is the common, acceptable outcome.
+    }
+    expect(recovered).not.toBe('legacy backup text')
   })
 })