feat: implement proto-gen platform

- Config loader with env var expansion and validation
- SQLite database with tasks and toolchain_versions tables
- Gitea REST API client for repository and branch operations
- K8s client for Job lifecycle management (with noop fallback for local dev)
- REST API: tasks CRUD, retry, plugins, version management
- Worker/scheduler with polling, concurrency control, and job tracking
- Static frontend: generate, tasks, settings pages
- Toolchain images: Go and Node.js Dockerfiles with entrypoint scripts
- Helm chart with deployment, service, configmap, ingress, PVC
- Multi-stage Dockerfile for service
- Unit tests for config, database, gitclient, k8s, api, worker
- E2E tests for idempotency, version switch, failure recovery

internal/database/tasks.go

@@ -0,0 +1,97 @@
+package database
+
+import (
+	"database/sql"
+	"fmt"
+	"time"
+
+	"proto-gen/internal/models"
+)
+
+func (db *DB) CreateTask(task *models.Task) error {
+	now := time.Now().UTC().Format(time.RFC3339)
+	_, err := db.conn.Exec(`
+		INSERT INTO tasks (id, status, language, proto_repo, proto_branch, target_repo, toolchain_image, created_at, updated_at)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+		task.ID, task.Status, task.Language, task.ProtoRepo, task.ProtoBranch,
+		task.TargetRepo, task.ToolchainImage, now, now,
+	)
+	return err
+}
+
+func (db *DB) GetTask(id string) (*models.Task, error) {
+	var t models.Task
+	var createdAt, updatedAt string
+	err := db.conn.QueryRow(`
+		SELECT id, status, language, proto_repo, proto_branch, proto_commit, target_repo,
+		       toolchain_image, image_digest, result_commit, error, log, retries, created_at, updated_at
+		FROM tasks WHERE id = ?`, id,
+	).Scan(&t.ID, &t.Status, &t.Language, &t.ProtoRepo, &t.ProtoBranch, &t.ProtoCommit,
+		&t.TargetRepo, &t.ToolchainImage, &t.ImageDigest, &t.ResultCommit,
+		&t.Error, &t.Log, &t.Retries, &createdAt, &updatedAt)
+	if err == sql.ErrNoRows {
+		return nil, fmt.Errorf("task not found: %s", id)
+	}
+	if err != nil {
+		return nil, err
+	}
+	t.CreatedAt, _ = time.Parse(time.RFC3339, createdAt)
+	t.UpdatedAt, _ = time.Parse(time.RFC3339, updatedAt)
+	return &t, nil
+}
+
+func (db *DB) UpdateTask(task *models.Task) error {
+	now := time.Now().UTC().Format(time.RFC3339)
+	_, err := db.conn.Exec(`
+		UPDATE tasks SET status=?, proto_commit=?, image_digest=?, result_commit=?,
+		       error=?, log=?, retries=?, updated_at=?
+		WHERE id=?`,
+		task.Status, task.ProtoCommit, task.ImageDigest, task.ResultCommit,
+		task.Error, task.Log, task.Retries, now, task.ID,
+	)
+	return err
+}
+
+func (db *DB) ListTasks(status string, limit, offset int) ([]*models.Task, error) {
+	query := `SELECT id, status, language, proto_repo, proto_branch, proto_commit, target_repo,
+	          toolchain_image, image_digest, result_commit, error, log, retries, created_at, updated_at
+	          FROM tasks`
+	var args []interface{}
+	if status != "" {
+		query += ` WHERE status = ?`
+		args = append(args, status)
+	}
+	query += ` ORDER BY created_at DESC LIMIT ? OFFSET ?`
+	args = append(args, limit, offset)
+
+	rows, err := db.conn.Query(query, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var tasks []*models.Task
+	for rows.Next() {
+		var t models.Task
+		var createdAt, updatedAt string
+		if err := rows.Scan(&t.ID, &t.Status, &t.Language, &t.ProtoRepo, &t.ProtoBranch,
+			&t.ProtoCommit, &t.TargetRepo, &t.ToolchainImage, &t.ImageDigest,
+			&t.ResultCommit, &t.Error, &t.Log, &t.Retries, &createdAt, &updatedAt); err != nil {
+			return nil, err
+		}
+		t.CreatedAt, _ = time.Parse(time.RFC3339, createdAt)
+		t.UpdatedAt, _ = time.Parse(time.RFC3339, updatedAt)
+		tasks = append(tasks, &t)
+	}
+	return tasks, nil
+}
+
+func (db *DB) GetPendingTasks(limit int) ([]*models.Task, error) {
+	return db.ListTasks(string(models.StatusPending), limit, 0)
+}
+
+func (db *DB) HasRunningTask(targetRepo string) (bool, error) {
+	var count int
+	err := db.conn.QueryRow(`SELECT COUNT(*) FROM tasks WHERE target_repo = ? AND status = 'running'`, targetRepo).Scan(&count)
+	return count > 0, err
+}