fix(desktop): count cookies the import could not decrypt

Rows `decryptChromiumValue` could not read were dropped without a trace, so an
import that recovered a fraction of the database still reported a clean
success. They now reach the user as part of the skipped total.

This matters most on Linux, where records written under a keyring-derived
`v11` key are unreadable unless that secret is reachable — see the note in
`ChromiumKeys`.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: juliusmarminge

apps/desktop/src/preview/BrowserImport/BrowserImport.ts

@@ -144,7 +144,7 @@ export const make = Effect.gen(function* BrowserImportMake() {
       });
     }
 
-    const cookies = yield* readChromiumCookies({
+    const read = yield* readChromiumCookies({
       cookieDatabasePath: cookieDatabasePath(definition, paths, requestedProfile.directory),
       keychainService: definition.keychainService,
       keychainAccount: definition.keychainAccount,
@@ -172,8 +172,10 @@ export const make = Effect.gen(function* BrowserImportMake() {
     // Written one at a time rather than in parallel: Chromium's cookie store
     // serialises writes anyway, and a rejected cookie should only cost itself.
     let imported = 0;
-    let skipped = 0;
-    for (const cookie of cookies) {
+    // Rows the reader could not decrypt are already lost cookies, so they
+    // count as skipped rather than vanishing from the tally.
+    let skipped = read.undecryptable;
+    for (const cookie of read.cookies) {
       const written = yield* Effect.tryPromise({
         try: () =>
           session.cookies.set({

apps/desktop/src/preview/BrowserImport/ChromiumCookies.ts

@@ -236,6 +236,16 @@ const decryptValue = (encrypted: Uint8Array, key: Buffer, domain: string): strin
   }
 };
 
+/**
+ * What a reader produces: the cookies it could recover, and how many stored
+ * rows it could not. The count reaches the user as part of the skipped total
+ * rather than disappearing.
+ */
+export interface CookieReadResult {
+  readonly cookies: ReadonlyArray<ChromiumCookie>;
+  readonly undecryptable: number;
+}
+
 export interface ChromiumCookieSource {
   readonly cookieDatabasePath: string;
   readonly keychainService: string;
@@ -302,9 +312,16 @@ export const readChromiumCookies = Effect.fn("ChromiumCookies.readChromiumCookie
   );
 
   const cookies: ChromiumCookie[] = [];
+  // Counted, not swallowed. A row we hold no usable key for is a cookie the
+  // user does not get, and reporting an import that quietly dropped most of
+  // its rows as a clean success is the worst of the options.
+  let undecryptable = 0;
   for (const row of rows) {
     const value = decryptValue(row.encrypted_value, key, row.host_key);
-    if (value === null) continue;
+    if (value === null) {
+      undecryptable += 1;
+      continue;
+    }
     const secure = row.is_secure === 1;
     const scope = cookieScope(row.host_key, row.path, secure);
     cookies.push({
@@ -319,5 +336,5 @@ export const readChromiumCookies = Effect.fn("ChromiumCookies.readChromiumCookie
       sameSite: sameSiteFromColumn(row.samesite),
     });
   }
-  return cookies satisfies ReadonlyArray<ChromiumCookie>;
+  return { cookies, undecryptable } satisfies CookieReadResult;
 });