gmail sync: don't retry on overquota, import what we have

- OVERQUOTA from Gmail now continues to import step instead of retrying
- partial sync completion email tells user to try again in a few hours
- engine syncs handler meta to job on completion for richer notifications

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/servers/queue/engine.ts

@@ -218,6 +218,7 @@ async function runJob(job: Job) {
   if (final && final.status === 'running') {
     final.status = 'completed';
     final.completedAt = Date.now();
+    final.meta = { ...final.meta, ...sharedMeta };
     await writeJob(final);
     console.log(`[queue] Job ${final.id} completed`);
     if (final.notify !== false) await notifyCompletion(final);

src/servers/queue/handlers/gmail-sync.ts

@@ -268,19 +268,29 @@ const gmailSyncHandler: JobHandler = {
           await readLoop;
 
           if (exitCode !== 0) {
-            console.error(`[gmail-sync] mbsync failed`);
             const isOverquota = stderrBuf.includes('OVERQUOTA');
             const isAuthFail = stderrBuf.includes('AUTHENTICATIONFAILED') || stderrBuf.includes('Invalid credentials');
-            if (isOverquota || isAuthFail) {
-              const emailCount = await countMaildirFiles(maildirPath);
-              ctx.meta.gmailSyncRecoverable = true;
-              ctx.meta.gmailSyncEmailCount = emailCount;
-              ctx.meta.gmailSyncIsAuthFail = isAuthFail;
-            }
-            throw new Error(`mbsync exited with code ${exitCode}: ${stderrBuf.slice(-500)}`);
-          }
 
-          console.log('[gmail-sync] mbsync completed successfully');
+            if (isOverquota) {
+              // Gmail throttled us — don't retry, just import what we have
+              const emailCount = await countMaildirFiles(maildirPath);
+              console.log(`[gmail-sync] Gmail OVERQUOTA — proceeding to import ${emailCount} downloaded emails`);
+              ctx.meta.gmailSyncPartial = true;
+              ctx.meta.gmailSyncEmailCount = emailCount;
+              // Fall through to import step
+            } else {
+              console.error(`[gmail-sync] mbsync failed`);
+              if (isAuthFail) {
+                const emailCount = await countMaildirFiles(maildirPath);
+                ctx.meta.gmailSyncRecoverable = true;
+                ctx.meta.gmailSyncEmailCount = emailCount;
+                ctx.meta.gmailSyncIsAuthFail = true;
+              }
+              throw new Error(`mbsync exited with code ${exitCode}: ${stderrBuf.slice(-500)}`);
+            }
+          } else {
+            console.log('[gmail-sync] mbsync completed successfully');
+          }
         } finally {
           // Always clean up config (contains password)
           await unlink(configPath).catch(() => {});