Initial scaffold: API service, K8s operator, and CRDs

Forgebot is a K8s operator + API service for dispatching AI agent
jobs from git forge commands. Includes:

- CRDs: AgentPool, AgentTask, ProviderQueue, RepositoryBinding
- API server with webhook handler, task queue, and comment proxy
- Operator controllers for task scheduling and job management
- Gitea provider with webhook parsing and signature verification
- PostgreSQL database with auto-migration
- Woodpecker CI pipelines and multi-stage Dockerfiles

internal/database/migrations.go

@@ -0,0 +1,35 @@
+package database
+
+import "context"
+
+func (db *DB) migrate() error {
+	_, err := db.Pool.Exec(context.Background(), `
+		CREATE TABLE IF NOT EXISTS tasks (
+			id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+			parent_task_id  UUID REFERENCES tasks(id),
+			command         TEXT NOT NULL,
+			skill           TEXT NOT NULL DEFAULT '',
+			repository      TEXT NOT NULL,
+			ref             TEXT NOT NULL,
+			issue_number    INTEGER NOT NULL DEFAULT 0,
+			pr_number       INTEGER NOT NULL DEFAULT 0,
+			comment_id      BIGINT NOT NULL DEFAULT 0,
+			body            TEXT NOT NULL DEFAULT '',
+			author          TEXT NOT NULL,
+			extra_tools     TEXT[] NOT NULL DEFAULT '{}',
+			status          TEXT NOT NULL DEFAULT 'pending',
+			pool_ref        TEXT NOT NULL DEFAULT '',
+			job_name        TEXT NOT NULL DEFAULT '',
+			result          TEXT NOT NULL DEFAULT '',
+			error_message   TEXT NOT NULL DEFAULT '',
+			created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+			started_at      TIMESTAMPTZ,
+			completed_at    TIMESTAMPTZ
+		);
+
+		CREATE INDEX IF NOT EXISTS idx_tasks_status ON tasks(status);
+		CREATE INDEX IF NOT EXISTS idx_tasks_repository ON tasks(repository);
+		CREATE INDEX IF NOT EXISTS idx_tasks_parent ON tasks(parent_task_id);
+	`)
+	return err
+}