fix. harden Go review flow

Fix runner bootstrap and auth handling, preserve queued SHAs, make event/job acceptance atomic, fence stale runs, correct retries and prompts, add fake end-to-end coverage, and fix deployment defaults.

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

migrations/0001_initial.sql

@@ -1,3 +1,57 @@
--- The Go migrator creates this logical schema with dialect-specific SQL.
--- This file documents the compatibility baseline: webhook_events, review_jobs,
--- review_runs, and bot_comments with the constraints described in README.md.
+-- MariaDB baseline schema. The Go startup migrator emits equivalent SQLite SQL.
+CREATE TABLE IF NOT EXISTS webhook_events (
+  id BIGINT AUTO_INCREMENT PRIMARY KEY,
+  delivery_id VARCHAR(255) NULL UNIQUE,
+  event_name VARCHAR(128) NOT NULL,
+  repo VARCHAR(255) NOT NULL,
+  comment_id BIGINT NULL,
+  payload_sha256 VARCHAR(64) NOT NULL,
+  created_at DATETIME(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),
+  UNIQUE KEY uq_webhook_events_repo_comment (repo, comment_id)
+) ENGINE=InnoDB;
+
+CREATE TABLE IF NOT EXISTS review_jobs (
+  id BIGINT AUTO_INCREMENT PRIMARY KEY,
+  repo VARCHAR(255) NOT NULL,
+  pr_number INT NOT NULL,
+  head_sha VARCHAR(64) NOT NULL,
+  trigger_comment_id BIGINT NOT NULL,
+  command VARCHAR(64) NOT NULL,
+  command_args TEXT NULL,
+  requested_by VARCHAR(255) NOT NULL,
+  status VARCHAR(32) NOT NULL,
+  last_error TEXT NULL,
+  result_json JSON NULL,
+  created_at DATETIME(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),
+  updated_at DATETIME(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),
+  started_at DATETIME(6) NULL,
+  finished_at DATETIME(6) NULL,
+  UNIQUE KEY uq_review_jobs_repo_trigger_comment (repo, trigger_comment_id),
+  KEY ix_review_jobs_lookup (repo, pr_number, head_sha, status, created_at)
+) ENGINE=InnoDB;
+
+CREATE TABLE IF NOT EXISTS review_runs (
+  id BIGINT AUTO_INCREMENT PRIMARY KEY,
+  job_id BIGINT NOT NULL,
+  status VARCHAR(32) NOT NULL,
+  runner_container_id VARCHAR(128) NULL,
+  result_json JSON NULL,
+  error_message TEXT NULL,
+  started_at DATETIME(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),
+  finished_at DATETIME(6) NULL,
+  CONSTRAINT fk_review_runs_job FOREIGN KEY (job_id) REFERENCES review_jobs(id) ON DELETE CASCADE,
+  KEY ix_review_runs_job_status (job_id, status)
+) ENGINE=InnoDB;
+
+CREATE TABLE IF NOT EXISTS bot_comments (
+  id BIGINT AUTO_INCREMENT PRIMARY KEY,
+  repo VARCHAR(255) NOT NULL,
+  pr_number INT NOT NULL,
+  head_sha VARCHAR(64) NOT NULL,
+  gitea_comment_id BIGINT NOT NULL,
+  marker VARCHAR(255) NOT NULL,
+  created_at DATETIME(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),
+  updated_at DATETIME(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),
+  UNIQUE KEY uq_bot_comments_marker (repo, pr_number, marker),
+  KEY ix_bot_comments_repo_pr (repo, pr_number)
+) ENGINE=InnoDB;