refactor: address high-priority debt and publish to PyPI

- Fix TOCTOU race conditions by wrapping read-modify-write cycles
  under single-file locks in execution_state, portfolio_service,
  precheck_state, state_manager, and precheck_service.
- Add missing test coverage (96 tests total):
  - test_review_service.py (15 tests)
  - test_check_api.py (6 tests)
  - test_external_gate.py main branches (+10 tests)
  - test_trade_execution.py new commands (+8 tests)
- Unify all agent-consumed JSON messages to English.
- Config-ize hardcoded values (volume filter, schema_version) via
  get_user_config with sensible defaults.
- Add 1-hour TTL to exchange cache with force_new override.
- Add ruff and mypy to dev dependencies; fix all type errors.
- Add __all__ declarations to 11 service modules.
- Sync README with new commands, config tuning docs, and PyPI badge.
- Publish package as coinhunter==1.0.0 on PyPI with MIT license.
- Deprecate coinhunter-cli==1.0.1 with runtime warning.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/coinhunter/services/execution_state.py

@@ -1,17 +1,25 @@
 """Execution state helpers (decision deduplication, executions.json)."""
 import hashlib
 
-from ..runtime import get_runtime_paths
-from .file_utils import load_json_locked, save_json_locked
-from .trade_common import bj_now_iso
+__all__ = [
+    "default_decision_id",
+    "load_executions",
+    "save_executions",
+    "record_execution_state",
+    "get_execution_state",
+]
 
-PATHS = get_runtime_paths()
-EXECUTIONS_FILE = PATHS.executions_file
-EXECUTIONS_LOCK = PATHS.executions_lock
+from ..runtime import get_runtime_paths
+from .file_utils import load_json_locked, read_modify_write_json, save_json_locked
+
+
+def _paths():
+    return get_runtime_paths()
 
 
 def default_decision_id(action: str, argv_tail: list[str]) -> str:
     from datetime import datetime
+
     from .trade_common import CST
 
     now = datetime.now(CST)
@@ -22,17 +30,24 @@ def default_decision_id(action: str, argv_tail: list[str]) -> str:
 
 
 def load_executions() -> dict:
-    return load_json_locked(EXECUTIONS_FILE, EXECUTIONS_LOCK, {"executions": {}}).get("executions", {})
+    paths = _paths()
+    data = load_json_locked(paths.executions_file, paths.executions_lock, {"executions": {}})
+    return data.get("executions", {})  # type: ignore[no-any-return]
 
 
 def save_executions(executions: dict):
-    save_json_locked(EXECUTIONS_FILE, EXECUTIONS_LOCK, {"executions": executions})
+    paths = _paths()
+    save_json_locked(paths.executions_file, paths.executions_lock, {"executions": executions})
 
 
 def record_execution_state(decision_id: str, payload: dict):
-    executions = load_executions()
-    executions[decision_id] = payload
-    save_executions(executions)
+    paths = _paths()
+    read_modify_write_json(
+        paths.executions_file,
+        paths.executions_lock,
+        {"executions": {}},
+        lambda data: data.setdefault("executions", {}).__setitem__(decision_id, payload) or data,
+    )
 
 
 def get_execution_state(decision_id: str):