feat(profile): user-profile feature registry + builder (phase A)

Centralizes user-level features (completion_rate_30d, dismiss_rate_30d,
mean_dwell_ms_30d, preferred_hour, tip_volume_30d) in a TS registry that
owns both definition and SQL aggregation, since the data lives in the
TS-owned SQLite tables (tip_views/tip_feedback). Lazy TTL refresh keeps
recommend latency bounded; values persist in user_profile_features (KV).

ml/serving accepts profile_features on /score + /generate but does not
yet consume them — extending the bandit feature vector changes D and
resets every user's learned state, so that's a deliberate phase-B step.

Includes ml/features/profile_schema.py as a contract mirror with a sync
test that diffs name sets against registry.ts.

ADR-0011 records the data-locality reasoning (registry in TS, not Python
as the issue originally suggested).

Phase B (deferred): event-driven incremental updates, bandit consumption
with state migration, admin per-user profile page, staleness alerts.

Refs #81.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ml/features/test_profile_schema.py

@@ -0,0 +1,41 @@
+"""Smoke test for profile_schema mirror (#81 phase A).
+
+The TS registry in services/api/src/profile/registry.ts is the source of truth.
+This test checks the names listed here match the registry by reading the TS
+file and grepping for `name: '...'`. Crude but cheap, and it catches the
+common rename/add-without-mirror failure mode.
+"""
+from __future__ import annotations
+import re
+from pathlib import Path
+
+from ml.features.profile_schema import PROFILE_FEATURES, feature_names
+
+
+REGISTRY_PATH = Path(__file__).resolve().parents[2] / "services" / "api" / "src" / "profile" / "registry.ts"
+
+
+def _ts_registry_names() -> set[str]:
+    text = REGISTRY_PATH.read_text(encoding="utf-8")
+    # Each FEATURES entry has `name: 'something_30d',`. Extract every match.
+    return set(re.findall(r"name:\s*'([a-zA-Z0-9_]+)'", text))
+
+
+def test_python_mirror_matches_ts_registry():
+    py_names = feature_names()
+    ts_names = _ts_registry_names()
+    assert py_names == ts_names, (
+        f"Profile feature names drifted between TS registry and Python mirror.\n"
+        f"  in Python only: {sorted(py_names - ts_names)}\n"
+        f"  in TS only:     {sorted(ts_names - py_names)}"
+    )
+
+
+def test_profile_schema_no_duplicates():
+    names = [f.name for f in PROFILE_FEATURES]
+    assert len(names) == len(set(names)), f"duplicate names: {names}"
+
+
+def test_profile_schema_dtypes_known():
+    for f in PROFILE_FEATURES:
+        assert f.dtype in {"numeric", "categorical"}