fix(db): make task checkout atomic

src/main/database/migrations/v53-v53.ts

@@ -0,0 +1,77 @@
+import log from "electron-log/main.js";
+import type { Migration, MigrationDeps } from "./types";
+import { nowIso, tableExists } from "./types";
+
+export function createMigrationsV53V53(deps: MigrationDeps): Migration[] {
+  const { db } = deps;
+  return [
+    {
+      version: 53,
+      name: "task_leases_restore_run_fk",
+      fn: () => {
+        if (!tableExists(db, "task_leases")) {
+          log.info("[migration v53] task_leases table missing; nothing to do");
+          return;
+        }
+
+        const danglingLeases = db.prepare(
+          `SELECT l.task_id AS taskId, l.run_id AS runId
+             FROM task_leases l
+             LEFT JOIN runs r ON r.id = l.run_id
+            WHERE r.id IS NULL`,
+        ).all() as Array<{ taskId: string; runId: string }>;
+
+        if (danglingLeases.length > 0) {
+          const ts = nowIso();
+          const repairTask = db.prepare(
+            `UPDATE tasks
+                SET active_run_id = CASE WHEN active_run_id = ? THEN NULL ELSE active_run_id END,
+                    checkout_run_id = CASE WHEN checkout_run_id = ? THEN NULL ELSE checkout_run_id END,
+                    execution_locked_at = CASE
+                      WHEN active_run_id = ? OR checkout_run_id = ? THEN NULL
+                      ELSE execution_locked_at
+                    END,
+                    updated_at = ?
+              WHERE id = ?`,
+          );
+          for (const lease of danglingLeases) {
+            repairTask.run(lease.runId, lease.runId, lease.runId, lease.runId, ts, lease.taskId);
+          }
+          db.prepare(
+            `DELETE FROM task_leases
+              WHERE run_id NOT IN (SELECT id FROM runs)`,
+          ).run();
+          log.warn(
+            `[migration v53] removed ${danglingLeases.length} dangling task lease(s) before restoring run_id FK`,
+          );
+        }
+
+        db.exec("PRAGMA defer_foreign_keys = ON");
+        db.exec(`
+          CREATE TABLE task_leases_v53 (
+            task_id TEXT PRIMARY KEY REFERENCES tasks(id) ON DELETE CASCADE,
+            run_id TEXT NOT NULL REFERENCES runs(id) ON DELETE CASCADE,
+            acquired_at TEXT NOT NULL,
+            expires_at TEXT NOT NULL,
+            checkout_run_id TEXT,
+            UNIQUE(task_id, run_id)
+          )
+        `);
+        db.exec(`
+          INSERT INTO task_leases_v53
+            (task_id, run_id, acquired_at, expires_at, checkout_run_id)
+          SELECT task_id, run_id, acquired_at, expires_at, checkout_run_id
+            FROM task_leases
+        `);
+        db.exec("DROP INDEX IF EXISTS idx_task_leases_expires_at");
+        db.exec("DROP TABLE task_leases");
+        db.exec("ALTER TABLE task_leases_v53 RENAME TO task_leases");
+        db.exec(
+          "CREATE INDEX IF NOT EXISTS idx_task_leases_expires_at ON task_leases(expires_at)",
+        );
+
+        log.info("[migration v53] task_leases.run_id FK restored");
+      },
+    },
+  ];
+}