Add GitHub MCP support to agent mode

- Parse --allowedTools from claude_args to detect when user wants GitHub MCPs
- Wire up github_inline_comment server in prepareMcpConfig for PR contexts
- Update agent mode to use prepareMcpConfig instead of manual config
- Add comprehensive tests for parseAllowedTools edge cases
- Fix TypeScript types to support both entity and automation contexts

test/modes/parse-tools.test.ts

@@ -0,0 +1,69 @@
+import { describe, test, expect } from "bun:test";
+import { parseAllowedTools } from "../../src/modes/agent/parse-tools";
+
+describe("parseAllowedTools", () => {
+  test("parses unquoted tools", () => {
+    const args = "--allowedTools mcp__github__*,mcp__github_comment__*";
+    expect(parseAllowedTools(args)).toEqual([
+      "mcp__github__*",
+      "mcp__github_comment__*",
+    ]);
+  });
+
+  test("parses double-quoted tools", () => {
+    const args = '--allowedTools "mcp__github__*,mcp__github_comment__*"';
+    expect(parseAllowedTools(args)).toEqual([
+      "mcp__github__*",
+      "mcp__github_comment__*",
+    ]);
+  });
+
+  test("parses single-quoted tools", () => {
+    const args = "--allowedTools 'mcp__github__*,mcp__github_comment__*'";
+    expect(parseAllowedTools(args)).toEqual([
+      "mcp__github__*",
+      "mcp__github_comment__*",
+    ]);
+  });
+
+  test("returns empty array when no allowedTools", () => {
+    const args = "--someOtherFlag value";
+    expect(parseAllowedTools(args)).toEqual([]);
+  });
+
+  test("handles empty string", () => {
+    expect(parseAllowedTools("")).toEqual([]);
+  });
+
+  test("handles duplicate --allowedTools flags", () => {
+    const args = "--allowedTools --allowedTools mcp__github__*";
+    // Should not match the first one since the value is another flag
+    expect(parseAllowedTools(args)).toEqual([]);
+  });
+
+  test("handles typo --alloedTools", () => {
+    const args = "--alloedTools mcp__github__*";
+    expect(parseAllowedTools(args)).toEqual([]);
+  });
+
+  test("handles multiple flags with allowedTools in middle", () => {
+    const args = '--flag1 value1 --allowedTools "mcp__github__*" --flag2 value2';
+    expect(parseAllowedTools(args)).toEqual(["mcp__github__*"]);
+  });
+
+  test("trims whitespace from tool names", () => {
+    const args = "--allowedTools 'mcp__github__* , mcp__github_comment__* '";
+    expect(parseAllowedTools(args)).toEqual([
+      "mcp__github__*",
+      "mcp__github_comment__*",
+    ]);
+  });
+
+  test("handles tools with special characters", () => {
+    const args = '--allowedTools "mcp__github__create_issue,mcp__github_comment__update"';
+    expect(parseAllowedTools(args)).toEqual([
+      "mcp__github__create_issue",
+      "mcp__github_comment__update",
+    ]);
+  });
+});