docs+skills: add main UI/UX visual-truth PRD and skill links

.agents/skills/rlm-mem/brain/scripts/test_layered_writer.py

@@ -0,0 +1,107 @@
+"""
+Tests for append-only layered JSONL writer with locking.
+
+Run: python -m unittest brain.scripts.test_layered_writer -v
+"""
+
+import json
+import tempfile
+import threading
+import unittest
+from pathlib import Path
+
+from brain.scripts.layered_memory_store import LayeredMemoryStore
+from brain.scripts.memory_policy import MemoryPolicy
+
+
+class TestLayeredWriter(unittest.TestCase):
+    def test_append_only_writer_preserves_existing_lines(self):
+        with tempfile.TemporaryDirectory() as tmpdir:
+            project_root = Path(tmpdir)
+            policy = MemoryPolicy(project_root=project_root)
+            store = LayeredMemoryStore(policy=policy, agent_id="agent-a")
+
+            first_id = store.append_entry(
+                layer="project_agent",
+                record={
+                    "id": "rec-1",
+                    "created_at": "2026-02-11T00:00:00Z",
+                    "scope": "project_agent",
+                    "agent_id": "agent-a",
+                    "entry_type": "fact",
+                    "content": "first",
+                    "project_id": "rlm-mem",
+                },
+            )
+            second_id = store.append_entry(
+                layer="project_agent",
+                record={
+                    "id": "rec-2",
+                    "created_at": "2026-02-11T00:00:01Z",
+                    "scope": "project_agent",
+                    "agent_id": "agent-a",
+                    "entry_type": "note",
+                    "content": "second",
+                    "project_id": "rlm-mem",
+                },
+            )
+
+            self.assertEqual(first_id, "rec-1")
+            self.assertEqual(second_id, "rec-2")
+
+            target = project_root / ".agents" / "memory" / "agents" / "agent-a" / "memory.jsonl"
+            lines = target.read_text(encoding="utf-8").splitlines()
+            self.assertEqual(len(lines), 2)
+            self.assertEqual(json.loads(lines[0])["id"], "rec-1")
+            self.assertEqual(json.loads(lines[1])["id"], "rec-2")
+
+    def test_concurrent_writes_keep_valid_jsonl_and_expected_count(self):
+        with tempfile.TemporaryDirectory() as tmpdir:
+            project_root = Path(tmpdir)
+            policy = MemoryPolicy(
+                project_root=project_root,
+                write_layers=["project_agent", "project_global"],
+            )
+            store = LayeredMemoryStore(policy=policy, agent_id="agent-b")
+
+            writes_per_thread = 40
+            thread_count = 8
+            errors: list[Exception] = []
+
+            def worker(thread_idx: int) -> None:
+                for item_idx in range(writes_per_thread):
+                    try:
+                        store.append_entry(
+                            layer="project_global",
+                            record={
+                                "id": f"t{thread_idx}-r{item_idx}",
+                                "created_at": "2026-02-11T00:00:00Z",
+                                "scope": "project_global",
+                                "entry_type": "fact",
+                                "content": f"thread-{thread_idx}-row-{item_idx}",
+                                "project_id": "rlm-mem",
+                            },
+                        )
+                    except Exception as exc:  # pragma: no cover - asserted below
+                        errors.append(exc)
+
+            threads = [threading.Thread(target=worker, args=(i,)) for i in range(thread_count)]
+            for t in threads:
+                t.start()
+            for t in threads:
+                t.join()
+
+            self.assertEqual(errors, [])
+
+            target = project_root / ".agents" / "memory" / "global" / "memory.jsonl"
+            lines = target.read_text(encoding="utf-8").splitlines()
+            self.assertEqual(len(lines), writes_per_thread * thread_count)
+
+            for line in lines:
+                parsed = json.loads(line)
+                self.assertIn("id", parsed)
+                self.assertIn("content", parsed)
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=2)