feat(tools): enforce skill capabilities and secret scopes

src/tools/types.ts

@@ -8,6 +8,8 @@ export interface Tool {
   name: string;
   description: string;
   inputSchema: ToolInputSchema;
+  /** Secret scopes required to execute this tool (optional). */
+  requiredSecretScopes?: string[];
   execute(args: unknown): Promise<ToolResult>;
 }