feat: build each doc kind with its own MkDocs config and site

tests/cli/test_build_api.py

@@ -1,4 +1,4 @@
-import json
+import json
 from pathlib import Path
 
 from docforge.cli.main import cli
@@ -55,8 +55,10 @@ def test_api_build_full_flow(
         index = (api_dir / "index.md").read_text(encoding="utf-8")
         assert '<swagger-ui src="openapi.json"/>' in index
 
-        config = (cwd / "mkdocs.yml").read_text(encoding="utf-8")
-        assert "docs_dir: docs" in config
+        config = (cwd / "docs" / "mkdocs.api.yml").read_text(encoding="utf-8")
+        assert "docs_dir: api" in config
+        assert "site_dir: ../site/api" in config
+        assert "- API Reference: index.md" in config
         assert "site_name: Aetoskia Auth Server" in config
         assert "site_description: Auth docs" in config
         assert "site_author: Aetoskia Dev Team" in config
@@ -90,10 +92,9 @@ def test_api_build_rejects_site_name_override(cli_runner):
         assert "cannot be overridden" in result.output
 
 
-def test_api_build_combined_with_mkdocs_allows_site_name_for_lib(
+def test_api_build_combined_with_mkdocs_emits_separate_configs(
     cli_runner, mock_mkdocs_build, mock_mkdocs_load_config
 ):
-    # site_name is accepted when --mkdocs is also present (lib mode owns it)
     with cli_runner.isolated_filesystem():
         cwd = Path.cwd()
 
@@ -105,13 +106,7 @@ def test_api_build_combined_with_mkdocs_allows_site_name_for_lib(
         spec_path = _write_spec(cwd)
 
         nav_file = cwd / "docforge.nav.yml"
-        nav_file.write_text(
-            "home: lib/testpkg/index.md\n"
-            "groups:\n"
-            "  API:\n"
-            "    - api/index.md\n",
-            encoding="utf-8",
-        )
+        nav_file.write_text("home: lib/testpkg/index.md\ngroups: {}\n")
 
         result = cli_runner.invoke(
             cli,
@@ -128,7 +123,20 @@ def test_api_build_combined_with_mkdocs_allows_site_name_for_lib(
 
         assert result.exit_code == 0, result.output
 
-        config = (cwd / "mkdocs.yml").read_text(encoding="utf-8")
-        assert "docs_dir: docs" in config
-        assert "swagger-ui-tag" in config
-        assert "mkdocstrings" in config
+        lib_config = cwd / "docs" / "mkdocs.lib.yml"
+        api_config = cwd / "docs" / "mkdocs.api.yml"
+        assert lib_config.exists()
+        assert api_config.exists()
+
+        lib_text = lib_config.read_text(encoding="utf-8")
+        assert "docs_dir: lib" in lib_text
+        assert "site_dir: ../site/lib" in lib_text
+        assert "Home: testpkg/index.md" in lib_text
+
+        api_text = api_config.read_text(encoding="utf-8")
+        assert "docs_dir: api" in api_text
+        assert "site_dir: ../site/api" in api_text
+        assert "- API Reference: index.md" in api_text
+        assert "site_name: Aetoskia Auth Server" in api_text
+        assert "swagger-ui-tag" in api_text
+        assert "mkdocstrings" in lib_text