fix: code audit — security, correctness, and robustness fixes

Security:
- Path traversal: validate user_id, case_id, skill_name against safe regex
- Input sanitization in memory.py and skills.py file path construction

Correctness:
- ISR timezone: replace hardcoded UTC+3 with ZoneInfo("Asia/Jerusalem") for DST
- save_rule: use EspoCrmApiError.status_code instead of fragile string matching
- Background tasks: store references to prevent GC before completion
- Lock race: use dict.setdefault() for atomic lock creation
- Version: health.py now matches main.py (0.2.0)
- Skill names: normalized to lowercase for dedup consistency

Build:
- Dockerfile: install from pyproject.toml instead of hardcoded pip list
- Remove unused mcp>=1.0.0 dependency from pyproject.toml

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/services/memory.py

@@ -5,6 +5,7 @@ from __future__ import annotations
 import asyncio
 import logging
 import os
+import re
 import tempfile
 from pathlib import Path
 
@@ -18,14 +19,21 @@ PROFILE_MAX_CHARS = 1500
 CASE_MEMORY_MAX_CHARS = 2500
 ENTRY_DELIMITER = "\n§\n"
 
+_SAFE_ID_RE = re.compile(r"^[a-zA-Z0-9_-]+$")
+
 # Per-path locks for thread-safe writes
 _locks: dict[str, asyncio.Lock] = {}
 
 
+def _safe_id(value: str) -> str:
+    """Validate that an ID is safe for use in file paths."""
+    if not value or not _SAFE_ID_RE.match(value):
+        raise ValueError(f"Invalid ID for file path: {value!r}")
+    return value
+
+
 def _get_lock(path: str) -> asyncio.Lock:
-    if path not in _locks:
-        _locks[path] = asyncio.Lock()
-    return _locks[path]
+    return _locks.setdefault(path, asyncio.Lock())
 
 
 def _read_file(path: str) -> str:
@@ -75,17 +83,17 @@ def _truncate(content: str, max_chars: int) -> str:
 
 def load_user_profile(user_id: str) -> str:
     """Load the per-lawyer profile. Returns empty string if none exists."""
-    return _read_file(f"{PROFILES_DIR}/{user_id}.md")
+    return _read_file(f"{PROFILES_DIR}/{_safe_id(user_id)}.md")
 
 
 def load_case_memory(case_id: str) -> str:
     """Load the per-case memory. Returns empty string if none exists."""
-    return _read_file(f"{CASES_DIR}/{case_id}/memory.md")
+    return _read_file(f"{CASES_DIR}/{_safe_id(case_id)}/memory.md")
 
 
 async def update_user_profile(user_id: str, action: str, content: str, match: str = "") -> str:
     """Add, replace, or remove an entry in the lawyer's profile."""
-    path = f"{PROFILES_DIR}/{user_id}.md"
+    path = f"{PROFILES_DIR}/{_safe_id(user_id)}.md"
     async with _get_lock(path):
         current = _read_file(path)
         entries = _entries(current)
@@ -129,7 +137,7 @@ async def update_user_profile(user_id: str, action: str, content: str, match: st
 
 async def update_case_memory(case_id: str, action: str, content: str, match: str = "") -> str:
     """Add, replace, or remove an entry in the case memory."""
-    path = f"{CASES_DIR}/{case_id}/memory.md"
+    path = f"{CASES_DIR}/{_safe_id(case_id)}/memory.md"
     async with _get_lock(path):
         current = _read_file(path)
         entries = _entries(current)