refactor(extension-*,stage-tamagotchi,stage-ui,server-*): rename to extension, improve DX (#1892)

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by-agent: Codex

packages/server-shared/src/errors.ts

@@ -2,9 +2,9 @@ export const ServerErrorMessages = {
   invalidEventFormat: 'invalid event format',
   invalidToken: 'invalid token',
   mustAuthenticateBeforeAnnouncing: 'must authenticate before announcing',
-  moduleAnnounceIdentityInvalid: 'module identity must include kind=plugin and a plugin id for event \'module:announce\'',
-  moduleAnnounceIndexInvalid: 'the field \'index\' must be a non-negative integer for event \'module:announce\'',
-  moduleAnnounceNameInvalid: 'the field \'name\' must be a non-empty string for event \'module:announce\'',
+  moduleAnnounceIdentityInvalid: 'extension module identity must include an extension id for event \'extension:module:announce\'',
+  moduleAnnounceIndexInvalid: 'the field \'index\' must be a non-negative integer for event \'extension:module:announce\'',
+  moduleAnnounceNameInvalid: 'the field \'name\' must be a non-empty string for event \'extension:module:announce\'',
   moduleConsumerEventInvalid: 'the field \'event\' must be a non-empty string for event consumer registration',
   moduleNotFound: 'module not found, it hasn\'t announced itself or the name is incorrect',
   noConsumerRegistered: 'no consumer registered for requested event delivery',

packages/server-shared/src/types/websocket/events.ts

@@ -1,9 +1,9 @@
-import type { ModuleIdentity, ProtocolEvents, RouteConfig, WebSocketEventSource } from '@proj-airi/plugin-protocol/types'
+import type { MetadataEventSource, ProtocolEvents, RouteConfig, WebSocketEventSource } from '@proj-airi/plugin-protocol/types'
 
 export * from '@proj-airi/plugin-protocol/types'
 
 export interface WebSocketEventBaseMetadata {
-  source?: ModuleIdentity
+  source?: MetadataEventSource
   event?: {
     id?: string
     parentId?: string
@@ -18,7 +18,7 @@ export interface WebSocketBaseEvent<T, D, S extends string = string> {
    */
   source?: WebSocketEventSource | S
   metadata: {
-    source: ModuleIdentity
+    source: MetadataEventSource
     event: {
       id: string
       parentId?: string