fix(config): 完成生产配置向 config.toml 的迁移

deployments/systemd/bat-api.env.example

@@ -1,9 +1,11 @@
-# Optional overrides for bluearchive-toolkit-bat-api.service.
+# Optional process-environment overrides for bluearchive-toolkit-bat-api.service.
 #
 # Install as:
 #   sudo install -o root -g root -m 0644 deployments/systemd/bat-api.env.example /etc/bluearchive-toolkit/bat-api.env
 #
 # Production contract:
+#   - systemd injects these values as process environment variables through
+#     EnvironmentFile; bat-api does not read this file as dotenv.
 #   - bat-api runs in the same server/container environment as Rust bat.
 #   - The current resource_root comes from bat.sock RPC.
 #   - Do not set BAT_API_RESOURCE_ROOT in production; it is only for local
@@ -21,7 +23,6 @@ BAT_API_REQUIRE_INDEXED=true
 BAT_API_VERIFY_SIZE=true
 BAT_API_RPC_TIMEOUT=30s
 BAT_API_REFRESH_INTERVAL=1m
-BAT_API_SKIP_ENV_FILE=1
 BAT_API_AUTH_QUERY_PARAM=bat_token
 # BAT_API_AUTH_TOKEN=
 # BAT_API_AUTH_EXEMPT_PATHS=/healthz,/readyz

deployments/systemd/bluearchive-toolkit-bat-api.service

@@ -17,7 +17,9 @@ Environment=BAT_API_REQUIRE_INDEXED=true
 Environment=BAT_API_VERIFY_SIZE=true
 Environment=BAT_API_RPC_TIMEOUT=30s
 Environment=BAT_API_REFRESH_INTERVAL=1m
-Environment=BAT_API_SKIP_ENV_FILE=1
+# This is an external systemd EnvironmentFile injection, not an application
+# dotenv file. bat-api only reads config.toml beside its executable plus the
+# process environment supplied here.
 EnvironmentFile=-/etc/bluearchive-toolkit/bat-api.env
 ExecStart=/opt/bluearchive-toolkit/bin/bat-api
 Restart=on-failure