fix(plugins): normalize legacy boolean settings before schema validation (#588)

The news plugin's schema turned global.dynamic_duration from a boolean
into an {enabled, min_duration_seconds, ...} object. Installs that have
not saved the news settings since still hold `true`, so every start
logged "Plugin news config does not match its schema (loading anyway):
Field 'global.dynamic_duration': Expected type object, got bool" and
flagged news degraded.

The settings form already reads such a boolean as {"enabled": <bool>}
(render_nested_section in plugin_config.html) and the next save writes
the object. The loader did not. It now applies the same rule before
merging schema defaults and validating, so the defaults fill in the rest
of the object and the plugin receives it in the new shape.

The rule lives in schema_manager.legacy_bool_as_object /
normalize_legacy_booleans. It applies at any depth of nested objects
but not inside arrays, matching the form, and only to a real bool under
an object-typed property with an `enabled` child. Every other mismatch
still warns. A parity test renders the template macro against the helper
so the two cannot drift.

Nothing is written to config.json at load: the normalization is in
memory, and the next save of the plugin's settings persists the object.

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

src/plugin_system/plugin_manager.py

@@ -22,7 +22,7 @@ from src.logging_config import get_logger
 from src.plugin_system.plugin_loader import PluginLoader
 from src.plugin_system.plugin_executor import PluginExecutor
 from src.plugin_system.plugin_state import PluginStateManager, PluginState
-from src.plugin_system.schema_manager import SchemaManager
+from src.plugin_system.schema_manager import SchemaManager, normalize_legacy_booleans
 from src.common.permission_utils import (
     ensure_directory_permissions,
     get_plugin_dir_mode
@@ -351,6 +351,7 @@ class PluginManager:
                 config = {}
             
             # Check if plugin has a config schema
+            schema = None
             schema_path = self.schema_manager.get_schema_path(plugin_id)
             if schema_path is None:
                 # Schema file doesn't exist
@@ -368,6 +369,24 @@ class PluginManager:
                         f"The schema may be invalid. Please verify the schema file at: {schema_path}"
                     )
 
+            # A plugin that turned an on/off boolean into an {enabled, ...}
+            # object still finds the boolean in config.json until the user saves
+            # its settings form, which carries it over (plugin_config.html).
+            # Read it the same way here, before the defaults fill in the rest
+            # of the object and before schema validation, so the plugin doesn't
+            # start with a schema warning and a degraded flag. In memory only:
+            # config.json is written by saves, never by loading a plugin.
+            if schema:
+                upgraded: List[str] = []
+                config = normalize_legacy_booleans(config, schema, upgraded)
+                if upgraded:
+                    self.logger.info(
+                        "Plugin %s: reading legacy boolean setting %s as "
+                        "{\"enabled\": ...}; saving the plugin's settings "
+                        "stores the new shape",
+                        plugin_id, ", ".join(upgraded),
+                    )
+
             # Merge config with schema defaults to ensure all defaults are applied
             try:
                 defaults = self.schema_manager.generate_default_config(plugin_id, use_cache=True)