TypeScript: add extensions to tsconfig and fix type errors (#12781)

* TypeScript: add extensions to tsconfig and fix type errors

- Add extensions/**/* to tsconfig.json includes
- Export ProviderAuthResult, AnyAgentTool from plugin-sdk
- Fix optional chaining for messageActions across channels
- Add missing type imports (MSTeamsConfig, GroupPolicy, etc.)
- Add type annotations for provider auth handlers
- Fix undici/fetch type compatibility in zalo proxy
- Correct ChannelAccountSnapshot property usage
- Add type casts for tool registrations
- Extract usage view styles and types to separate files

* TypeScript: fix optional debug calls and handleAction guards

src/config/types.channels.ts

@@ -23,6 +23,19 @@ export type ChannelDefaultsConfig = {
   heartbeat?: ChannelHeartbeatVisibilityConfig;
 };
 
+/**
+ * Base type for extension channel config sections.
+ * Extensions can use this as a starting point for their channel config.
+ */
+export type ExtensionChannelConfig = {
+  enabled?: boolean;
+  allowFrom?: string | string[];
+  dmPolicy?: string;
+  groupPolicy?: GroupPolicy;
+  accounts?: Record<string, unknown>;
+  [key: string]: unknown;
+};
+
 export type ChannelsConfig = {
   defaults?: ChannelDefaultsConfig;
   whatsapp?: WhatsAppConfig;
@@ -33,5 +46,7 @@ export type ChannelsConfig = {
   signal?: SignalConfig;
   imessage?: IMessageConfig;
   msteams?: MSTeamsConfig;
-  [key: string]: unknown;
+  // Extension channels use dynamic keys - use ExtensionChannelConfig in extensions
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  [key: string]: any;
 };