fix(db): jobs.update writes only patched columns; late progress cannot resurrect a finished job

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/db/src/repos/jobs.ts

@@ -44,13 +44,21 @@ export function jobsRepo(db: Db) {
       }
     },
 
+    /**
+     * Single UPDATE writing only the patched columns (plus updated_at). A progress-only patch
+     * (progress and/or message) is guarded by status = 'running', so a late report on a
+     * finished job is a no-op.
+     */
     async update(id: string, patch: JobPatch): Promise<void> {
-      const cur = await get(id);
-      if (!cur) return;
-      const next = { ...cur, ...patch };
-      await db.sql`UPDATE jobs SET status = ${next.status}, progress = ${next.progress}, message = ${next.message ?? null},
-        result_json = ${next.result === null || next.result === undefined ? null : JSON.stringify(next.result)},
-        error = ${next.error ?? null}, updated_at = ${new Date().toISOString()} WHERE id = ${id}`;
+      const set: Record<string, unknown> = { updated_at: new Date().toISOString() };
+      if (patch.status !== undefined) set.status = patch.status;
+      if (patch.progress !== undefined) set.progress = patch.progress;
+      if (patch.message !== undefined) set.message = patch.message;
+      if (patch.result !== undefined) set.result_json = patch.result === null ? null : JSON.stringify(patch.result);
+      if (patch.error !== undefined) set.error = patch.error;
+      const progressOnly = patch.status === undefined && patch.result === undefined && patch.error === undefined;
+      if (progressOnly) await db.sql`UPDATE jobs SET ${db.sql(set)} WHERE id = ${id} AND status = 'running'`;
+      else await db.sql`UPDATE jobs SET ${db.sql(set)} WHERE id = ${id}`;
     },
 
     async list(kind?: string): Promise<JobRecord[]> {