feat(mcp): add MCP JSON renderer and CLI support, update tests accordingly

- Add MCPRenderer to generate MCP-native JSON bundles (index.json, nav.json, modules/*.json)
- Expose MCPRenderer via public API and CLI (`generate-mcp` command)
- Replace Markdown-based MCP output with structured JSON resources
- Update MCP renderer type stubs to match new JSON-based implementation
- Refactor MCP tests to validate JSON content, bundle structure, and navigation
- Fix MCP module coverage test to use explicit project_root for reliable discovery

tests/renderers/mcp/test_mcp_module_coverage.py

@@ -5,11 +5,13 @@ from docforge import MCPRenderer
 
 
 def test_mcp_emits_all_modules(tmp_path: Path) -> None:
+    project_root = Path(__file__).resolve().parents[3]
     loader = GriffeLoader()
     discovered_paths = discover_module_paths(
         "docforge",
-        Path(r"C:\Users\vishe\WorkSpace\code\aetos\doc-forge"),
+        project_root=project_root,
     )
+
     project = loader.load_project(discovered_paths)
 
     renderer = MCPRenderer()
@@ -17,13 +19,16 @@ def test_mcp_emits_all_modules(tmp_path: Path) -> None:
 
     emitted = {
         p.relative_to(tmp_path).as_posix()
-        for p in tmp_path.rglob("*.md")
+        for p in (tmp_path / "modules").rglob("*.json")
     }
 
     expected = {
-        m.path.replace(".", "/") + ".md"
+        f"modules/{m.path}.json"
         for m in project.get_all_modules()
     }
 
     missing = expected - emitted
-    assert not missing, f"Missing MCP resources for modules: {missing}"
+    assert not missing, f"Missing MCP module JSON files: {missing}"
+
+    # also assert nav.json exists
+    assert (tmp_path / "nav.json").exists()