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_content.py

@@ -1,3 +1,4 @@
+import json
 from pathlib import Path
 
 from docforge import MCPRenderer
@@ -13,6 +14,8 @@ def test_mcp_file_content(tmp_path: Path):
 
     renderer.generate_sources(project, out_dir)
 
-    content = (out_dir / "testpkg" / "mod.md").read_text()
+    module_file = out_dir / "modules" / "testpkg.mod.json"
+    payload = json.loads(module_file.read_text())
 
-    assert "# Module `testpkg.mod`" in content
+    assert payload["module"] == "testpkg.mod"
+    assert payload["content"]["path"] == "testpkg.mod"

tests/renderers/mcp/test_mcp_idempotency.py

@@ -12,9 +12,9 @@ def test_mcp_idempotent(tmp_path: Path):
     renderer = MCPRenderer()
 
     renderer.generate_sources(project, out_dir)
-    first = (out_dir / "testpkg" / "mod.md").read_text()
+    first = (out_dir / "modules" / "testpkg.mod.json").read_text()
 
     renderer.generate_sources(project, out_dir)
-    second = (out_dir / "testpkg" / "mod.md").read_text()
+    second = (out_dir / "modules" / "testpkg.mod.json").read_text()
 
     assert first == second

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()

tests/renderers/mcp/test_mcp_structure.py

@@ -14,5 +14,10 @@ def test_mcp_directory_structure(tmp_path: Path):
 
     renderer.generate_sources(project, out_dir)
 
-    assert (out_dir / "testpkg.md").exists()
-    assert (out_dir / "testpkg" / "sub.md").exists()
+    # Bundle-level files
+    assert (out_dir / "index.json").exists()
+    assert (out_dir / "nav.json").exists()
+
+    # Module resources
+    assert (out_dir / "modules" / "testpkg.json").exists()
+    assert (out_dir / "modules" / "testpkg.sub.json").exists()