feat(worker): add durable background jobs

migrations/000026_add_background_jobs.down.sql

@@ -0,0 +1,7 @@
+DROP INDEX IF EXISTS idx_background_jobs_idempotency_key_unique;
+DROP INDEX IF EXISTS idx_background_jobs_idempotency_key;
+DROP INDEX IF EXISTS idx_background_jobs_locked_at;
+DROP INDEX IF EXISTS idx_background_jobs_job_type;
+DROP INDEX IF EXISTS idx_background_jobs_ready;
+DROP TABLE IF EXISTS background_jobs;
+

migrations/000026_add_background_jobs.up.sql

@@ -0,0 +1,29 @@
+CREATE TABLE IF NOT EXISTS background_jobs (
+    id BIGSERIAL PRIMARY KEY,
+    queue VARCHAR(100) NOT NULL DEFAULT 'default',
+    job_type VARCHAR(150) NOT NULL,
+    payload JSONB NOT NULL DEFAULT '{}',
+    status VARCHAR(50) NOT NULL DEFAULT 'queued',
+    priority INTEGER NOT NULL DEFAULT 0,
+    attempts INTEGER NOT NULL DEFAULT 0,
+    max_attempts INTEGER NOT NULL DEFAULT 3,
+    scheduled_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
+    locked_at TIMESTAMP WITH TIME ZONE,
+    locked_by VARCHAR(150),
+    idempotency_key VARCHAR(255),
+    last_error TEXT,
+    finished_at TIMESTAMP WITH TIME ZONE,
+    failed_at TIMESTAMP WITH TIME ZONE,
+    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
+    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS idx_background_jobs_ready
+    ON background_jobs(status, queue, scheduled_at, priority DESC, id);
+CREATE INDEX IF NOT EXISTS idx_background_jobs_job_type ON background_jobs(job_type);
+CREATE INDEX IF NOT EXISTS idx_background_jobs_locked_at ON background_jobs(locked_at);
+CREATE INDEX IF NOT EXISTS idx_background_jobs_idempotency_key ON background_jobs(idempotency_key);
+CREATE UNIQUE INDEX IF NOT EXISTS idx_background_jobs_idempotency_key_unique
+    ON background_jobs(idempotency_key)
+    WHERE idempotency_key IS NOT NULL AND idempotency_key <> '';
+