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/gitclient/gitea.go

@@ -0,0 +1,136 @@
+package gitclient
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+type giteaClient struct {
+	baseURL    string
+	token      string
+	httpClient *http.Client
+}
+
+func NewClient(baseURL, token string) GitClient {
+	return &giteaClient{
+		baseURL:    baseURL,
+		token:      token,
+		httpClient: &http.Client{Timeout: 30 * time.Second},
+	}
+}
+
+func (c *giteaClient) doRequest(method, path string, body interface{}) ([]byte, error) {
+	u := c.baseURL + "/api/v1" + path
+
+	var bodyReader io.Reader
+	if body != nil {
+		data, err := json.Marshal(body)
+		if err != nil {
+			return nil, fmt.Errorf("marshaling body: %w", err)
+		}
+		bodyReader = bytes.NewReader(data)
+	}
+
+	req, err := http.NewRequest(method, u, bodyReader)
+	if err != nil {
+		return nil, fmt.Errorf("creating request: %w", err)
+	}
+	req.Header.Set("Authorization", "token "+c.token)
+	if body != nil {
+		req.Header.Set("Content-Type", "application/json")
+	}
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("executing request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("reading response: %w", err)
+	}
+
+	if resp.StatusCode >= 400 {
+		return nil, fmt.Errorf("gitea API error (%d): %s", resp.StatusCode, string(data))
+	}
+
+	return data, nil
+}
+
+func (c *giteaClient) ListRepositories(owner string) ([]Repository, error) {
+	data, err := c.doRequest("GET", "/repos/search?limit=50&owner="+url.QueryEscape(owner), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var result struct {
+		Data []Repository `json:"data"`
+	}
+	if err := json.Unmarshal(data, &result); err != nil {
+		return nil, fmt.Errorf("parsing response: %w", err)
+	}
+	return result.Data, nil
+}
+
+func (c *giteaClient) CreateRepository(owner, name, description string, private bool) (*Repository, error) {
+	body := map[string]interface{}{
+		"name":        name,
+		"description": description,
+		"private":     private,
+	}
+	data, err := c.doRequest("POST", "/user/repos", body)
+	if err != nil {
+		return nil, err
+	}
+
+	var repo Repository
+	if err := json.Unmarshal(data, &repo); err != nil {
+		return nil, fmt.Errorf("parsing response: %w", err)
+	}
+	return &repo, nil
+}
+
+func (c *giteaClient) GetRepository(owner, name string) (*Repository, error) {
+	data, err := c.doRequest("GET", "/repos/"+url.PathEscape(owner)+"/"+url.PathEscape(name), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var repo Repository
+	if err := json.Unmarshal(data, &repo); err != nil {
+		return nil, fmt.Errorf("parsing response: %w", err)
+	}
+	return &repo, nil
+}
+
+func (c *giteaClient) ListBranches(owner, repo string) ([]Branch, error) {
+	data, err := c.doRequest("GET", "/repos/"+url.PathEscape(owner)+"/"+url.PathEscape(repo)+"/branches", nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var branches []Branch
+	if err := json.Unmarshal(data, &branches); err != nil {
+		return nil, fmt.Errorf("parsing response: %w", err)
+	}
+	return branches, nil
+}
+
+func (c *giteaClient) GetBranch(owner, repo, branch string) (*Branch, error) {
+	data, err := c.doRequest("GET", "/repos/"+url.PathEscape(owner)+"/"+url.PathEscape(repo)+"/branches/"+url.PathEscape(branch), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var b Branch
+	if err := json.Unmarshal(data, &b); err != nil {
+		return nil, fmt.Errorf("parsing response: %w", err)
+	}
+	return &b, nil
+}