feat(telemetry): add isolated beta quality diagnostics and release identity

tests/unit_tests/test_build_revision_stamp.py

@@ -0,0 +1,30 @@
+"""Release artifacts must identify their actual source, not a branch label."""
+
+import ast
+import importlib.util
+from pathlib import Path
+
+import pytest
+
+ROOT = Path(__file__).resolve().parents[2]
+SPEC = importlib.util.spec_from_file_location('stamp_build_revision', ROOT / 'scripts/stamp_build_revision.py')
+assert SPEC is not None and SPEC.loader is not None
+MODULE = importlib.util.module_from_spec(SPEC)
+SPEC.loader.exec_module(MODULE)
+
+
+def test_stamp_accepts_full_revision(tmp_path):
+    target = tmp_path / 'src/langbot/_build_info.py'
+    target.parent.mkdir(parents=True)
+    revision = 'a1' * 20
+    assert MODULE.stamp(tmp_path, revision) == revision
+    assignments = [node for node in ast.parse(target.read_text()).body if isinstance(node, ast.Assign)]
+    assert len(assignments) == 1
+    assert ast.literal_eval(assignments[0].value) == revision
+
+
+@pytest.mark.parametrize('revision', ['main', 'abc123', 'A' * 40, 'a' * 39, 'a' * 41, '../secret', 'a' * 40 + '\n'])
+def test_stamp_rejects_non_revision_before_write(tmp_path, revision):
+    with pytest.raises(ValueError):
+        MODULE.stamp(tmp_path, revision)
+    assert not (tmp_path / 'src').exists()