feat: add local agent MCP tools and optional source-grounded AI answers

apps/desktop/tests/ai-state.test.mjs

@@ -0,0 +1,33 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import {AiRevision,aiConfigurationProblem,aiQuestionProblem,aiEndpointLabel,aiSourceEligible} from '../src/ai-state.ts';
+const config=()=>({enabled:false,base_url:'',model:'',api_key:null});
+
+test('optional generation is disabled initially and requires an explicit endpoint/model',()=>{
+  assert.match(aiConfigurationProblem(config()),/disabled/);
+  assert.match(aiConfigurationProblem({...config(),enabled:true}),/endpoint/);
+  assert.equal(aiConfigurationProblem({...config(),enabled:true,base_url:'http://localhost:1234/v1',model:'local-model'}),null);
+  assert.equal(aiConfigurationProblem({...config(),enabled:true,base_url:'https://chosen.example/v1',model:'chosen-model',api_key:'session-key'}),null);
+});
+test('unsafe URL credentials and query parameters cannot leak through configuration errors',()=>{
+  const secret='private-session-key';
+  for(const base_url of [`https://user:${secret}@example.com/v1`,`https://example.com/v1?key=${secret}`,'file:///secret']){
+    const error=aiConfigurationProblem({...config(),enabled:true,base_url,model:'m'});
+    assert.ok(error);assert.ok(!error.includes(secret));
+  }
+  assert.equal(aiEndpointLabel(`https://user:${secret}@example.com/v1?key=${secret}`),'https://example.com');
+});
+test('UTF8 byte budgets and actual text source types gate explicit questions',()=>{
+  assert.ok(aiQuestionProblem('界'.repeat(700)));
+  assert.equal(aiQuestionProblem('What notice is required?'),null);
+  assert.equal(aiSourceEligible({kind:'page',number:2}),true);
+  assert.equal(aiSourceEligible({kind:'timestamp_ms',number:100}),false);
+  assert.equal(aiSourceEligible({kind:'page',number:2},true),false);
+  assert.equal(aiSourceEligible(undefined),false);
+});
+test('selection/configuration changes invalidate older preparation and answers',()=>{
+  const revision=new AiRevision();revision.select('first:page2');const old=revision.current();
+  revision.select('second:page1');assert.equal(revision.accepts(old),false);
+  const selected=revision.current();revision.select('second:page1');assert.equal(revision.accepts(selected),true);
+  revision.invalidate();assert.equal(revision.accepts(selected),false);
+});