feat: add comprehensive integration tests for auto-mode-service

- Created git-test-repo helper for managing test git repositories
- Added 13 integration tests covering:
  - Worktree operations (create, error handling, non-worktree mode)
  - Feature execution (status updates, model selection, duplicate prevention)
  - Auto loop (start/stop, pending features, max concurrency, events)
  - Error handling (provider errors, continue after failures)
- Integration tests use real git operations with temporary repos
- All 416 tests passing with 72.65% overall coverage
- Service coverage improved: agent-service 58%, auto-mode-service 44%, feature-loader 66%

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

apps/server/tests/fixtures/configs.ts

@@ -0,0 +1,25 @@
+/**
+ * Configuration fixtures for testing Codex config manager
+ */
+
+export const tomlConfigFixture = `
+experimental_use_rmcp_client = true
+
+[mcp_servers.automaker-tools]
+command = "node"
+args = ["/path/to/server.js"]
+startup_timeout_sec = 10
+tool_timeout_sec = 60
+enabled_tools = ["UpdateFeatureStatus"]
+
+[mcp_servers.automaker-tools.env]
+AUTOMAKER_PROJECT_PATH = "/path/to/project"
+`;
+
+export const codexAuthJsonFixture = {
+  token: {
+    access_token: "test-access-token",
+    refresh_token: "test-refresh-token",
+    id_token: "test-id-token",
+  },
+};

apps/server/tests/fixtures/images.ts

@@ -0,0 +1,14 @@
+/**
+ * Image fixtures for testing image handling
+ */
+
+// 1x1 transparent PNG base64 data
+export const pngBase64Fixture =
+  "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg==";
+
+export const imageDataFixture = {
+  base64: pngBase64Fixture,
+  mimeType: "image/png",
+  filename: "test.png",
+  originalPath: "/path/to/test.png",
+};

apps/server/tests/fixtures/messages.ts

@@ -0,0 +1,62 @@
+/**
+ * Message fixtures for testing providers and lib utilities
+ */
+
+import type {
+  ConversationMessage,
+  ProviderMessage,
+  ContentBlock,
+} from "../../src/providers/types.js";
+
+export const conversationHistoryFixture: ConversationMessage[] = [
+  {
+    role: "user",
+    content: "Hello, can you help me?",
+  },
+  {
+    role: "assistant",
+    content: "Of course! How can I assist you today?",
+  },
+  {
+    role: "user",
+    content: [
+      { type: "text", text: "What is in this image?" },
+      {
+        type: "image",
+        source: { type: "base64", media_type: "image/png", data: "base64data" },
+      },
+    ],
+  },
+];
+
+export const claudeProviderMessageFixture: ProviderMessage = {
+  type: "assistant",
+  message: {
+    role: "assistant",
+    content: [{ type: "text", text: "This is a test response" }],
+  },
+};
+
+export const codexThinkingMessageFixture = {
+  type: "item.completed",
+  item: {
+    type: "reasoning",
+    text: "I need to analyze the problem first...",
+  },
+};
+
+export const codexCommandExecutionFixture = {
+  type: "item.completed",
+  item: {
+    type: "command_execution",
+    command: "ls -la",
+    aggregated_output: "total 12\ndrwxr-xr-x 3 user user 4096 Dec 13",
+  },
+};
+
+export const codexErrorFixture = {
+  type: "error",
+  data: {
+    message: "Authentication failed",
+  },
+};