fix(config): use the shared core-key list in the last three private copies

StartupValidator warned "Plugin 'auto_update' is enabled but not found" on
every display start with auto-update or a dim schedule on; the reserved
plugin-id check missed auto_update, sync, location and the rest; and
ConfigManager's (uncalled) orphan cleanup would have deleted display,
schedule and auto_update. All three now read src/core_config_keys.py, which
also gains CORE_SECRETS_KEYS for the github/youtube secrets sections.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/config_manager.py

@@ -29,6 +29,7 @@ import os
 import logging
 from pathlib import Path
 from typing import Dict, Any, Optional, List
+from src.core_config_keys import CORE_CONFIG_KEYS, CORE_SECRETS_KEYS
 from src.exceptions import ConfigError
 from src.logging_config import get_logger
 from src.config_manager_atomic import (
@@ -756,12 +757,13 @@ class ConfigManager:
             
             valid_set = set(valid_plugin_ids)
             
-            # Find orphaned plugins in main config
-            main_plugins = set(main_config.keys())
+            # Find orphaned plugins in main config. Core sections (display,
+            # schedule, auto_update, ...) are not plugins and never orphans.
+            main_plugins = set(main_config.keys()) - CORE_CONFIG_KEYS
             orphaned_main = main_plugins - valid_set
             
             # Find orphaned plugins in secrets config
-            secrets_plugins = set(secrets_config.keys())
+            secrets_plugins = set(secrets_config.keys()) - CORE_CONFIG_KEYS - CORE_SECRETS_KEYS
             orphaned_secrets = secrets_plugins - valid_set
             
             all_orphaned = orphaned_main | orphaned_secrets
@@ -815,8 +817,8 @@ class ConfigManager:
                 if not isinstance(plugin_config, dict):
                     continue
                 
-                # Skip non-plugin config sections
-                if plugin_id in ['display', 'schedule', 'timezone', 'plugin_system']:
+                # Skip core config sections
+                if plugin_id in CORE_CONFIG_KEYS:
                     continue
                 
                 schema = plugin_schema_manager.load_schema(plugin_id, use_cache=True)

src/core_config_keys.py

@@ -41,3 +41,13 @@ CORE_CONFIG_KEYS = frozenset({
     'vegas_excluded_plugins',
     'vegas_scroll_enabled',
 })
+
+#: Top-level keys of ``config_secrets.json`` that belong to the core rather than
+#: to a plugin: the GitHub token the Plugin Store reads, and the historical
+#: ``youtube`` section. Plugin secrets are namespaced by plugin id, so anything
+#: deciding whether a secrets section is a plugin's needs this as well as
+#: ``CORE_CONFIG_KEYS``.
+CORE_SECRETS_KEYS = frozenset({
+    'github',
+    'youtube',
+})

src/plugin_system/schema_manager.py

@@ -13,6 +13,8 @@ from typing import Any, Dict, List, Optional, Tuple
 import jsonschema
 from jsonschema import Draft7Validator, ValidationError
 
+from src.core_config_keys import CORE_CONFIG_KEYS
+
 
 def _renders_as_object(prop: Dict[str, Any]) -> bool:
     """``field_type == 'object'`` as ``plugin_config.html`` computes it.
@@ -698,10 +700,11 @@ class SchemaManager:
         """
         collisions = []
 
-        # Reserved top-level config keys that plugins should not use as IDs
-        reserved_keys = {
-            'display', 'schedule', 'timezone', 'plugin_system',
-            'display_modes', 'system', 'hardware', 'debug',
+        # Reserved top-level config keys that plugins should not use as IDs:
+        # every core section (src/core_config_keys.py), plus a few names that
+        # read as core even though no current section uses them.
+        reserved_keys = set(CORE_CONFIG_KEYS) | {
+            'display_modes', 'hardware', 'debug',
             'log_level', 'emulator', 'web_interface'
         }
 

src/startup_validator.py

@@ -8,6 +8,7 @@ Fails fast with clear error messages to prevent runtime issues.
 import os
 from typing import Any, List, Optional, Tuple
 from pathlib import Path
+from src.core_config_keys import CORE_CONFIG_KEYS
 from src.exceptions import ConfigError, PluginError, CacheError
 from src.logging_config import get_logger
 
@@ -275,8 +276,9 @@ class StartupValidator:
             
             # Check for enabled plugins that don't exist
             for plugin_id, plugin_config in config.items():
-                # Skip non-plugin config sections
-                if plugin_id in ['display', 'schedule', 'timezone', 'plugin_system']:
+                # Skip core sections: auto_update and dim_schedule have an
+                # 'enabled' key too, and are not plugins that went missing.
+                if plugin_id in CORE_CONFIG_KEYS:
                     continue
                 
                 if not isinstance(plugin_config, dict):