feat: optional LLM-based closet regeneration — bring-your-own endpoint

Adds mempalace/closet_llm.py as an OPTIONAL path for richer closet
generation. Regex closets remain the default and cover the local-first
promise; users who want LLM-quality topics can bring their own endpoint.

Configuration (env or CLI flag):
  LLM_ENDPOINT — OpenAI-compatible base URL (required)
  LLM_KEY      — bearer token (optional; local inference skips this)
  LLM_MODEL    — model name (required)

Works with Ollama, vLLM, llama.cpp servers, OpenAI, OpenRouter, and any
other provider that speaks OpenAI-compatible /chat/completions. Zero new
dependencies — uses stdlib urllib.

Replaces the original Anthropic-SDK-hardcoded version of this module
from Milla's branch (commit 935f657). Same prompt, same parsing, same
regenerate_closets flow; only the transport was generalised so the
feature doesn't lock users into a specific vendor or require API keys
for core memory operations (CLAUDE.md, "Local-first, zero API").

Includes 13 unit tests covering config resolution, request shape,
auth-header omission when no key is set, code-fence stripping, and
missing-config error path. All mocked — zero network calls in tests.

Co-Authored-By: MSL <232237854+milla-jovovich@users.noreply.github.com>

tests/test_closet_llm.py

@@ -0,0 +1,222 @@
+"""Unit tests for the optional LLM-based closet regeneration.
+
+These tests don't hit the network. They mock urllib to verify:
+- LLMConfig correctly reads env vars and CLI overrides
+- missing config is reported cleanly
+- the OpenAI-compatible request shape is correct
+- response parsing handles the standard chat-completions payload
+"""
+
+import io
+import json
+import os
+import tempfile
+from unittest.mock import patch
+
+import pytest
+
+from mempalace.closet_llm import (
+    LLMConfig,
+    _call_llm,
+    _parsed_to_closet_lines,
+    regenerate_closets,
+)
+
+
+# ── LLMConfig ─────────────────────────────────────────────────────────────
+
+
+class TestLLMConfig:
+    def test_reads_env_vars(self, monkeypatch):
+        monkeypatch.setenv("LLM_ENDPOINT", "http://localhost:11434/v1")
+        monkeypatch.setenv("LLM_KEY", "sk-abc")
+        monkeypatch.setenv("LLM_MODEL", "llama3:8b")
+        c = LLMConfig()
+        assert c.endpoint == "http://localhost:11434/v1"
+        assert c.key == "sk-abc"
+        assert c.model == "llama3:8b"
+
+    def test_cli_flags_override_env(self, monkeypatch):
+        monkeypatch.setenv("LLM_ENDPOINT", "http://env-endpoint/v1")
+        monkeypatch.setenv("LLM_MODEL", "env-model")
+        c = LLMConfig(endpoint="http://flag-endpoint/v1", model="flag-model")
+        assert c.endpoint == "http://flag-endpoint/v1"
+        assert c.model == "flag-model"
+
+    def test_trailing_slash_stripped(self):
+        c = LLMConfig(endpoint="http://foo/v1/", model="m")
+        assert c.endpoint == "http://foo/v1"
+
+    def test_missing_reports_required(self, monkeypatch):
+        monkeypatch.delenv("LLM_ENDPOINT", raising=False)
+        monkeypatch.delenv("LLM_KEY", raising=False)
+        monkeypatch.delenv("LLM_MODEL", raising=False)
+        c = LLMConfig()
+        missing = c.missing()
+        assert any("ENDPOINT" in m for m in missing)
+        assert any("MODEL" in m for m in missing)
+        # key is optional
+        assert not any("KEY" in m for m in missing)
+
+    def test_key_is_optional(self, monkeypatch):
+        monkeypatch.delenv("LLM_KEY", raising=False)
+        c = LLMConfig(endpoint="http://local/v1", model="m")
+        assert c.missing() == []
+
+
+# ── _parsed_to_closet_lines ──────────────────────────────────────────────
+
+
+class TestParsedToLines:
+    def test_topics_become_pointers(self):
+        parsed = {"topics": ["authentication", "jwt tokens"], "quotes": [], "summary": ""}
+        lines = _parsed_to_closet_lines(parsed, ["d1", "d2"], "Alice;Bob")
+        assert len(lines) == 2
+        assert "authentication|Alice;Bob|→d1,d2" in lines
+        assert "jwt tokens|Alice;Bob|→d1,d2" in lines
+
+    def test_quotes_and_summary_included(self):
+        parsed = {
+            "topics": ["t1"],
+            "quotes": ["[Igor] we ship Friday"],
+            "summary": "Release planning discussion",
+        }
+        lines = _parsed_to_closet_lines(parsed, ["d1"], "")
+        joined = "\n".join(lines)
+        assert "we ship Friday" in joined
+        assert "Release planning discussion" in joined
+
+    def test_caps_topics_at_15(self):
+        parsed = {"topics": [f"t{i}" for i in range(20)], "quotes": [], "summary": ""}
+        lines = _parsed_to_closet_lines(parsed, ["d1"], "")
+        assert len(lines) == 15
+
+
+# ── _call_llm (HTTP mocked) ──────────────────────────────────────────────
+
+
+class _FakeResp:
+    """Mimics urlopen's context-manager response."""
+
+    def __init__(self, payload: dict, status: int = 200):
+        self._body = json.dumps(payload).encode("utf-8")
+        self.status = status
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *a):
+        return False
+
+    def read(self):
+        return self._body
+
+
+class TestCallLLM:
+    def _make_cfg(self):
+        return LLMConfig(
+            endpoint="http://localhost:11434/v1", key="sk-test", model="llama3:8b"
+        )
+
+    def test_request_shape_and_parsing(self):
+        cfg = self._make_cfg()
+        captured = {}
+
+        def fake_urlopen(req, timeout=None):
+            captured["url"] = req.full_url
+            captured["headers"] = dict(req.header_items())
+            captured["body"] = json.loads(req.data.decode("utf-8"))
+            return _FakeResp(
+                {
+                    "choices": [
+                        {
+                            "message": {
+                                "content": json.dumps(
+                                    {
+                                        "topics": ["postgres"],
+                                        "quotes": ["[Igor] migrate now"],
+                                        "summary": "db migration",
+                                    }
+                                )
+                            }
+                        }
+                    ],
+                    "usage": {"prompt_tokens": 42, "completion_tokens": 17},
+                }
+            )
+
+        with patch("urllib.request.urlopen", side_effect=fake_urlopen):
+            parsed, usage = _call_llm(cfg, "/tmp/test.md", "w", "r", "content body")
+
+        assert parsed["topics"] == ["postgres"]
+        assert usage["prompt_tokens"] == 42
+        assert captured["url"] == "http://localhost:11434/v1/chat/completions"
+        # Authorization header is stored capitalized-then-lowercase depending on urllib version
+        auth_vals = {v for k, v in captured["headers"].items() if k.lower() == "authorization"}
+        assert "Bearer sk-test" in auth_vals
+        assert captured["body"]["model"] == "llama3:8b"
+        assert captured["body"]["messages"][0]["role"] == "user"
+
+    def test_omits_auth_header_when_no_key(self):
+        cfg = LLMConfig(endpoint="http://localhost:11434/v1", model="llama3:8b")
+        captured_headers = {}
+
+        def fake_urlopen(req, timeout=None):
+            captured_headers.update({k.lower(): v for k, v in req.header_items()})
+            return _FakeResp(
+                {
+                    "choices": [
+                        {"message": {"content": '{"topics":[],"quotes":[],"summary":""}'}}
+                    ],
+                    "usage": {"prompt_tokens": 0, "completion_tokens": 0},
+                }
+            )
+
+        with patch("urllib.request.urlopen", side_effect=fake_urlopen):
+            _call_llm(cfg, "/tmp/x", "w", "r", "c")
+
+        assert "authorization" not in captured_headers
+
+    def test_strips_code_fences(self):
+        cfg = self._make_cfg()
+        fenced = '```json\n{"topics":["t1"],"quotes":[],"summary":""}\n```'
+
+        def fake_urlopen(req, timeout=None):
+            return _FakeResp(
+                {
+                    "choices": [{"message": {"content": fenced}}],
+                    "usage": {"prompt_tokens": 1, "completion_tokens": 1},
+                }
+            )
+
+        with patch("urllib.request.urlopen", side_effect=fake_urlopen):
+            parsed, _ = _call_llm(cfg, "/tmp/x", "w", "r", "c")
+        assert parsed == {"topics": ["t1"], "quotes": [], "summary": ""}
+
+    def test_returns_none_on_invalid_json(self):
+        cfg = self._make_cfg()
+
+        def fake_urlopen(req, timeout=None):
+            return _FakeResp(
+                {
+                    "choices": [{"message": {"content": "not json at all"}}],
+                    "usage": {"prompt_tokens": 1, "completion_tokens": 1},
+                }
+            )
+
+        with patch("urllib.request.urlopen", side_effect=fake_urlopen):
+            parsed, usage = _call_llm(cfg, "/tmp/x", "w", "r", "c")
+        assert parsed is None
+
+
+# ── regenerate_closets error paths ───────────────────────────────────────
+
+
+class TestRegenerateClosets:
+    def test_missing_config_returns_error(self, monkeypatch):
+        monkeypatch.delenv("LLM_ENDPOINT", raising=False)
+        monkeypatch.delenv("LLM_MODEL", raising=False)
+        with tempfile.TemporaryDirectory() as palace:
+            result = regenerate_closets(palace)
+            assert result["error"] == "missing-config"
+            assert any("ENDPOINT" in m for m in result["missing"])