feat(plugins): hot reload des plugins sans relancer IdeA — use case ReloadPlugin (invalidation registry/catalogue, resultat hashes+changed), tools MCP d'administration plugin agent-facing (mcp/plugins.rs + PluginToolProvider), evenement domaine plugin_reloaded relaye sur le wire (dto/events), exposition openai_tools rafraichie, wiring app-tauri — #271/#269 (QA verte #273: application 32, mcp_server 38, openai_tools 10, plugin_install_load 5, plugin 10, wire 1 — 96 tests ciblés; app-tauri compile sans desktop runtime)

crates/domain/src/events.rs

@@ -61,6 +61,17 @@ pub enum DomainEvent {
         /// Installed version.
         version: PluginVersion,
     },
+    /// An installed plugin package was reloaded from its recorded source.
+    PluginReloaded {
+        /// Plugin id.
+        plugin_id: PluginId,
+        /// Content hash before the reload.
+        old_content_hash: String,
+        /// Content hash after the reload.
+        new_content_hash: String,
+        /// Whether the package contents changed.
+        changed: bool,
+    },
     /// A plugin was enabled.
     PluginEnabled {
         /// Plugin id.