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/static/style.css

@@ -0,0 +1,191 @@
+* {
+    margin: 0;
+    padding: 0;
+    box-sizing: border-box;
+}
+
+body {
+    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+    background: #f5f5f5;
+    color: #333;
+}
+
+nav {
+    background: #2c3e50;
+    padding: 1rem 2rem;
+    display: flex;
+    align-items: center;
+    gap: 2rem;
+}
+
+.logo {
+    color: #ecf0f1;
+    font-size: 1.5rem;
+    font-weight: bold;
+    text-decoration: none;
+}
+
+.nav-links a {
+    color: #bdc3c7;
+    text-decoration: none;
+    padding: 0.5rem 1rem;
+    border-radius: 4px;
+}
+
+.nav-links a:hover,
+.nav-links a.active {
+    color: #ecf0f1;
+    background: rgba(255,255,255,0.1);
+}
+
+main {
+    max-width: 900px;
+    margin: 2rem auto;
+    padding: 0 1rem;
+}
+
+h1 {
+    margin-bottom: 1.5rem;
+    color: #2c3e50;
+}
+
+h2 {
+    margin: 1.5rem 0 1rem;
+    color: #34495e;
+}
+
+.form-group {
+    margin-bottom: 1rem;
+}
+
+label {
+    display: block;
+    margin-bottom: 0.5rem;
+    font-weight: 500;
+}
+
+input, select {
+    width: 100%;
+    padding: 0.75rem;
+    border: 1px solid #ddd;
+    border-radius: 4px;
+    font-size: 1rem;
+}
+
+input:focus, select:focus {
+    outline: none;
+    border-color: #3498db;
+}
+
+small {
+    color: #7f8c8d;
+    font-size: 0.85rem;
+}
+
+button {
+    padding: 0.75rem 1.5rem;
+    border: none;
+    border-radius: 4px;
+    cursor: pointer;
+    font-size: 1rem;
+}
+
+.btn-primary {
+    background: #3498db;
+    color: white;
+}
+
+.btn-primary:hover {
+    background: #2980b9;
+}
+
+.btn-secondary {
+    background: #95a5a6;
+    color: white;
+}
+
+.btn-small {
+    padding: 0.25rem 0.75rem;
+    font-size: 0.85rem;
+    background: #e74c3c;
+    color: white;
+}
+
+.badge {
+    display: inline-block;
+    padding: 0.25rem 0.75rem;
+    border-radius: 12px;
+    color: white;
+    font-size: 0.85rem;
+    text-transform: capitalize;
+}
+
+.filters {
+    display: flex;
+    gap: 1rem;
+    margin-bottom: 1rem;
+}
+
+.filters select {
+    width: auto;
+}
+
+table {
+    width: 100%;
+    border-collapse: collapse;
+    background: white;
+    border-radius: 8px;
+    overflow: hidden;
+    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
+}
+
+th, td {
+    padding: 0.75rem 1rem;
+    text-align: left;
+    border-bottom: 1px solid #eee;
+}
+
+th {
+    background: #f8f9fa;
+    font-weight: 600;
+}
+
+code {
+    background: #f0f0f0;
+    padding: 0.15rem 0.4rem;
+    border-radius: 3px;
+    font-size: 0.9rem;
+}
+
+.message {
+    padding: 1rem;
+    margin-top: 1rem;
+    border-radius: 4px;
+}
+
+.message.success {
+    background: #d4edda;
+    color: #155724;
+}
+
+.message.error {
+    background: #f8d7da;
+    color: #721c24;
+}
+
+.hidden {
+    display: none;
+}
+
+.plugin-card {
+    background: white;
+    padding: 1rem;
+    margin-bottom: 1rem;
+    border-radius: 8px;
+    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
+}
+
+.plugin-card h3 {
+    margin-bottom: 0.5rem;
+    text-transform: uppercase;
+}