refactor(core): expose consequentialHint annotation

This allows `consequentialHint` to be passed to `ModelContext.registerTool`. From Angular's perspective, this is simply a pass-through option.

See: https://groups.google.com/a/chromium.org/g/chrome-ai-dev-preview/c/uHu5kfclbKw/m/dgorjfHPDgAJ

packages/core/src/webmcp/types.ts

@@ -75,6 +75,12 @@ export interface Annotations {
    * author of the tool.
    */
   untrustedContentHint?: boolean;
+
+  /**
+   * A hint that the tool will have consequential effects like mutating state or interacting
+   * with the external world.
+   */
+  consequentialHint?: boolean;
 }
 
 /**

packages/core/test/webmcp/declare_tool_spec.ts

@@ -79,6 +79,7 @@ describe('declareExperimentalWebMcpTool', () => {
         annotations: {
           readOnlyHint: true,
           untrustedContentHint: true,
+          consequentialHint: true,
         },
       },
       Injector.create({providers: []}),
@@ -89,6 +90,7 @@ describe('declareExperimentalWebMcpTool', () => {
         annotations: {
           readOnlyHint: true,
           untrustedContentHint: true,
+          consequentialHint: true,
         },
       }),
       jasmine.anything(),