feat: initial commit — Billo Release Agent (LangGraph)

LangGraph-based release automation agent with:
- PR discovery (webhook + polling)
- AI code review via Claude Code CLI (subscription-based)
- Auto-create Jira tickets for PRs without ticket ID
- Jira ticket lifecycle management (code review -> staging -> done)
- CI/CD pipeline trigger, polling, and approval gates
- Slack interactive messages with approval buttons
- Per-repo semantic versioning
- PostgreSQL persistence (threads, staging, releases)
- FastAPI API (webhooks, approvals, status, manual triggers)
- Docker Compose deployment

1069 tests, 95%+ coverage.

tests/api/test_dependencies.py

@@ -0,0 +1,149 @@
+"""Tests for API FastAPI dependencies. Written FIRST (TDD RED phase)."""
+
+from unittest.mock import MagicMock
+
+import pytest
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+from release_agent.api.dependencies import (
+    get_db_pool,
+    get_graphs,
+    get_settings,
+    get_staging_store,
+    get_tool_clients,
+)
+
+
+# ---------------------------------------------------------------------------
+# Helpers
+# ---------------------------------------------------------------------------
+
+def _make_app_with_state(**state_kwargs) -> FastAPI:
+    """Return a minimal FastAPI app with app.state attributes set."""
+    app = FastAPI()
+    for key, value in state_kwargs.items():
+        setattr(app.state, key, value)
+    return app
+
+
+# ---------------------------------------------------------------------------
+# get_settings
+# ---------------------------------------------------------------------------
+
+class TestGetSettings:
+    def test_returns_settings_from_state(self) -> None:
+        mock_settings = MagicMock()
+        app = _make_app_with_state(settings=mock_settings)
+
+        with TestClient(app) as client:
+            # We test the dependency directly by simulating a request
+            request = MagicMock()
+            request.app = app
+            result = get_settings(request)
+            assert result is mock_settings
+
+    def test_raises_when_settings_missing(self) -> None:
+        app = FastAPI()  # no state.settings
+
+        request = MagicMock()
+        request.app = app
+
+        with pytest.raises(AttributeError):
+            get_settings(request)
+
+
+# ---------------------------------------------------------------------------
+# get_graphs
+# ---------------------------------------------------------------------------
+
+class TestGetGraphs:
+    def test_returns_graphs_from_state(self) -> None:
+        mock_graphs = {"pr_completed": MagicMock(), "release": MagicMock()}
+        app = _make_app_with_state(graphs=mock_graphs)
+
+        request = MagicMock()
+        request.app = app
+        result = get_graphs(request)
+        assert result is mock_graphs
+
+    def test_raises_when_graphs_missing(self) -> None:
+        app = FastAPI()
+
+        request = MagicMock()
+        request.app = app
+
+        with pytest.raises(AttributeError):
+            get_graphs(request)
+
+
+# ---------------------------------------------------------------------------
+# get_tool_clients
+# ---------------------------------------------------------------------------
+
+class TestGetToolClients:
+    def test_returns_tool_clients_from_state(self) -> None:
+        mock_clients = MagicMock()
+        app = _make_app_with_state(tool_clients=mock_clients)
+
+        request = MagicMock()
+        request.app = app
+        result = get_tool_clients(request)
+        assert result is mock_clients
+
+    def test_raises_when_tool_clients_missing(self) -> None:
+        app = FastAPI()
+
+        request = MagicMock()
+        request.app = app
+
+        with pytest.raises(AttributeError):
+            get_tool_clients(request)
+
+
+# ---------------------------------------------------------------------------
+# get_staging_store
+# ---------------------------------------------------------------------------
+
+class TestGetStagingStore:
+    def test_returns_staging_store_from_state(self) -> None:
+        mock_store = MagicMock()
+        app = _make_app_with_state(staging_store=mock_store)
+
+        request = MagicMock()
+        request.app = app
+        result = get_staging_store(request)
+        assert result is mock_store
+
+    def test_raises_when_staging_store_missing(self) -> None:
+        app = FastAPI()
+
+        request = MagicMock()
+        request.app = app
+
+        with pytest.raises(AttributeError):
+            get_staging_store(request)
+
+
+# ---------------------------------------------------------------------------
+# get_db_pool
+# ---------------------------------------------------------------------------
+
+class TestGetDbPool:
+    def test_returns_db_pool_from_state(self) -> None:
+        mock_pool = MagicMock()
+        app = _make_app_with_state(db_pool=mock_pool)
+
+        request = MagicMock()
+        request.app = app
+        result = get_db_pool(request)
+        assert result is mock_pool
+
+    def test_raises_when_db_pool_missing(self) -> None:
+        app = FastAPI()
+
+        request = MagicMock()
+        request.app = app
+
+        with pytest.raises(AttributeError):
+            get_db_pool(request)