feat: switch config to JSONC + split secrets.json

Load business config as JSONC (comments + trailing commas) via an
in-repo stripper then stdlib json — no new deps. Default path prefers
config.jsonc, falls back to legacy config.json. Auth write-back targets
only sibling secrets.json so JSONC comments are never wiped; secrets
overlay merges on load. Examples, compose, Docker, docs, favsort and
tools all share the same loader. Phase A only — no DB settings migration.

reaction_board/cli.py

@@ -28,7 +28,7 @@ from .bilibili.auth_flow import AuthService
 from .bilibili.client import BilibiliClient, Pacer
 from .bilibili.provider import ClientProvider
 from .bilibili.search import SearchClient
-from .config import ConfigError, ConfigStore
+from .config import ConfigError, ConfigStore, default_config_path
 from .database import Database
 from .logging_json import JsonLogger
 from .notify.telegram import TelegramClient
@@ -42,7 +42,7 @@ from .services.up_profile import UpProfileService
 from .timeutil import next_daily_run, parse_hhmm, shanghai_date
 
 ROOT = Path(__file__).resolve().parent.parent
-DEFAULT_CONFIG = ROOT / "config.json"
+DEFAULT_CONFIG = default_config_path(ROOT)
 
 
 def _build_parser() -> argparse.ArgumentParser:
@@ -50,7 +50,7 @@ def _build_parser() -> argparse.ArgumentParser:
     common.add_argument(
         "--config",
         default=argparse.SUPPRESS,
-        help="配置文件路径（默认项目根目录 config.json）",
+        help="配置文件路径（默认优先 config.jsonc，否则 config.json）",
     )
 
     parser = argparse.ArgumentParser(
@@ -60,7 +60,7 @@ def _build_parser() -> argparse.ArgumentParser:
     parser.add_argument(
         "--config",
         default=str(DEFAULT_CONFIG),
-        help="配置文件路径（默认项目根目录 config.json）",
+        help="配置文件路径（默认优先 config.jsonc，否则 config.json）",
     )
     sub = parser.add_subparsers(dest="command", required=False)