test: add 106 unit + smoke tests, 93% coverage

- pytest + respx + pytest-cov added as dev dependencies
- tests/smoke/test_registration.py: verify all 66 tools registered and unique
- tests/unit/: 12 files covering every tool — HTTP method, URL, params/body, errors
- tests/config.test.json + conftest.py: zero-network test setup via GITEA_CONFIG
- CLAUDE.md: developer guide with testing philosophy, pyramid, and commands
- server/gitea_mcp.py: get_commit, list_pr_files tools added
- README.md: tool count corrected to 66

tests/unit/test_repos.py

@@ -0,0 +1,151 @@
+import json
+import pytest
+import httpx
+import respx
+from server.gitea_mcp import (
+    list_my_repos, search_repos, get_repo, create_repo, create_org_repo,
+    update_repo, delete_repo, fork_repo, set_repo_topics,
+)
+
+BASE = "https://gitea.test/api/v1"
+
+
+@respx.mock
+def test_list_my_repos_defaults():
+    route = respx.get(f"{BASE}/user/repos").mock(return_value=httpx.Response(200, json=[]))
+    list_my_repos()
+    assert route.called
+    params = dict(route.calls[0].request.url.params)
+    assert params["limit"] == "50"
+    assert params["page"] == "1"
+
+
+@respx.mock
+def test_list_my_repos_custom_page():
+    route = respx.get(f"{BASE}/user/repos").mock(return_value=httpx.Response(200, json=[]))
+    list_my_repos(limit=10, page=3)
+    assert route.called
+    params = dict(route.calls[0].request.url.params)
+    assert params["limit"] == "10"
+    assert params["page"] == "3"
+
+
+@respx.mock
+def test_search_repos():
+    route = respx.get(f"{BASE}/repos/search").mock(
+        return_value=httpx.Response(200, json={"data": []})
+    )
+    result = search_repos("myquery")
+    assert route.called
+    params = dict(route.calls[0].request.url.params)
+    assert params["q"] == "myquery"
+    assert params["limit"] == "20"
+
+
+@respx.mock
+def test_get_repo():
+    route = respx.get(f"{BASE}/repos/owner/myrepo").mock(
+        return_value=httpx.Response(200, json={"name": "myrepo", "full_name": "owner/myrepo"})
+    )
+    result = get_repo("owner", "myrepo")
+    assert route.called
+    assert result["name"] == "myrepo"
+
+
+@respx.mock
+def test_get_repo_not_found():
+    respx.get(f"{BASE}/repos/owner/missing").mock(
+        return_value=httpx.Response(404, json={"message": "not found"})
+    )
+    with pytest.raises(RuntimeError, match="404"):
+        get_repo("owner", "missing")
+
+
+@respx.mock
+def test_create_repo_defaults():
+    route = respx.post(f"{BASE}/user/repos").mock(
+        return_value=httpx.Response(201, json={"name": "newrepo"})
+    )
+    result = create_repo("newrepo")
+    assert route.called
+    body = json.loads(route.calls[0].request.content)
+    assert body["name"] == "newrepo"
+    assert body["private"] is True
+    assert body["auto_init"] is True
+    assert "description" not in body
+
+
+@respx.mock
+def test_create_repo_with_options():
+    route = respx.post(f"{BASE}/user/repos").mock(
+        return_value=httpx.Response(201, json={"name": "pub"})
+    )
+    create_repo("pub", description="A public repo", private=False, gitignores="Python")
+    body = json.loads(route.calls[0].request.content)
+    assert body["description"] == "A public repo"
+    assert body["private"] is False
+    assert body["gitignores"] == "Python"
+
+
+@respx.mock
+def test_create_org_repo():
+    route = respx.post(f"{BASE}/orgs/myorg/repos").mock(
+        return_value=httpx.Response(201, json={"name": "orgrepo"})
+    )
+    result = create_org_repo("myorg", "orgrepo")
+    assert route.called
+    body = json.loads(route.calls[0].request.content)
+    assert body["name"] == "orgrepo"
+
+
+@respx.mock
+def test_update_repo():
+    route = respx.patch(f"{BASE}/repos/owner/repo").mock(
+        return_value=httpx.Response(200, json={"name": "repo"})
+    )
+    update_repo("owner", "repo", description="updated")
+    assert route.called
+    body = json.loads(route.calls[0].request.content)
+    assert body["description"] == "updated"
+
+
+@respx.mock
+def test_delete_repo():
+    route = respx.delete(f"{BASE}/repos/owner/repo").mock(
+        return_value=httpx.Response(204)
+    )
+    result = delete_repo("owner", "repo")
+    assert route.called
+    assert result == {"success": True}
+
+
+@respx.mock
+def test_fork_repo():
+    route = respx.post(f"{BASE}/repos/upstream/repo/forks").mock(
+        return_value=httpx.Response(202, json={"name": "repo"})
+    )
+    fork_repo("upstream", "repo")
+    assert route.called
+
+
+@respx.mock
+def test_fork_repo_to_org():
+    route = respx.post(f"{BASE}/repos/upstream/repo/forks").mock(
+        return_value=httpx.Response(202, json={"name": "myfork"})
+    )
+    fork_repo("upstream", "repo", organization="myorg", new_repo_name="myfork")
+    body = json.loads(route.calls[0].request.content)
+    assert body["organization"] == "myorg"
+    assert body["name"] == "myfork"
+
+
+@respx.mock
+def test_set_repo_topics():
+    route = respx.put(f"{BASE}/repos/owner/repo/topics").mock(
+        return_value=httpx.Response(204)
+    )
+    result = set_repo_topics("owner", "repo", ["python", "mcp"])
+    assert route.called
+    body = json.loads(route.calls[0].request.content)
+    assert body["topics"] == ["python", "mcp"]
+    assert result == {"success": True}