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/graph/test_full_cycle.py

@@ -0,0 +1,53 @@
+"""Tests for graph/full_cycle.py.
+
+Tests that the full cycle graph composes pr_completed and release subgraphs
+correctly, and that the routing conditional edge works as expected.
+"""
+
+from release_agent.graph.full_cycle import build_full_cycle_graph
+from release_agent.graph.routing import should_continue_to_release
+
+
+class TestBuildFullCycleGraph:
+    def test_returns_compiled_graph(self) -> None:
+        graph = build_full_cycle_graph()
+        assert graph is not None
+
+    def test_graph_can_be_built_multiple_times(self) -> None:
+        graph1 = build_full_cycle_graph()
+        graph2 = build_full_cycle_graph()
+        assert graph1 is not None
+        assert graph2 is not None
+
+    def test_graph_has_get_graph_method(self) -> None:
+        graph = build_full_cycle_graph()
+        assert hasattr(graph, "get_graph") or hasattr(graph, "nodes")
+
+
+class TestFullCycleRouting:
+    """Test that the routing function used by full_cycle correctly
+    determines whether to continue to the release subgraph."""
+
+    def test_continue_when_flag_true_and_no_errors(self) -> None:
+        state = {"continue_to_release": True, "errors": []}
+        assert should_continue_to_release(state) == "yes"
+
+    def test_stop_when_flag_false(self) -> None:
+        state = {"continue_to_release": False}
+        assert should_continue_to_release(state) == "no"
+
+    def test_stop_when_flag_missing(self) -> None:
+        state = {}
+        assert should_continue_to_release(state) == "no"
+
+    def test_stop_when_errors_present(self) -> None:
+        state = {"continue_to_release": True, "errors": ["some error"]}
+        assert should_continue_to_release(state) == "no"
+
+    def test_stop_when_flag_true_but_errors_present(self) -> None:
+        state = {"continue_to_release": True, "errors": ["critical failure"]}
+        assert should_continue_to_release(state) == "no"
+
+    def test_continue_when_errors_empty_list(self) -> None:
+        state = {"continue_to_release": True, "errors": []}
+        assert should_continue_to_release(state) == "yes"