fix(newos4): connect to Ollama on first use, honest write_file, list_files sees /sys

Three defects, each re-probed first and covered by a test that is red on HEAD.

- ollama-manager.js: nothing connects at boot; only the Ollama tab button called connect(),
  so a user's first message died with "Ollama not connected. Use ollamaconnect first." even
  when the endpoint was healthy. New _ensureConnected() runs from chat(), chatStream() and
  chatWithTools(): one attempt, shared by concurrent callers, a "Connecting…" hint, and only
  then the error — which now says the endpoint is unreachable instead of telling the user to
  run a command they already expected to work.
- module-aiassist.js write_file tool: fs.writeFile()'s false return was dropped and the tool
  answered "File written: …" anyway, sending the model on to a read that found nothing
  (MAINT-012). It now returns "Write FAILED: … — parent directory missing or target is a
  directory; nothing was written".
- module-aiassist.js list_files tool: the hand-rolled walk over root.content never resolved
  the virtual mounts, so /sys — a directory the UI and `ls` both show — answered
  "Directory not found" (MAINT-011). It now uses fs.readDir(), which resolves mounts and
  returns null for a genuinely missing path.

Tests: modules/test/test-ai-fs-tools.js (7 asserts) and
modules/test/test-ollama-autoconnect.js (11 asserts). RED on HEAD: ai tools 4 passed/3 FAILED
(/sys → "Directory not found", write_file → "File written: …"), ollama 2 passed/9 FAILED
("Use ollamaconnect first"). GREEN now 7/7 and 11/11; maintain --fix reports "node tests 9/9 pass".
Live on v4.6.105: connectedBefore=false, _ensureConnected()=true in 41 ms, 37 models.

2 files changed, 172 insertions, 0 deletions

diff --git a/modules/test/test-ai-fs-tools.js b/modules/test/test-ai-fs-tools.js
new file mode 100644
index 0000000..c427783
--- /dev/null
+++ b/modules/test/test-ai-fs-tools.js
@@ -0,0 +1,74 @@
+// modules/test/test-ai-fs-tools.js — run: node
+// Proves MAINT-011 (list_files must see the virtual /sys mount) and MAINT-012
+// (write_file must not report success when the write was refused).
+const fsMod = require('fs'), path = require('path');
+const ROOT = path.join(__dirname, '..', 'core');
+const ls = {};
+global.localStorage = { getItem: k => (k in ls ? ls[k] : null), setItem: (k, v) => { ls[k] = String(v); }, removeItem: k => { delete ls[k]; } };
+global.indexedDB = { open() { throw new Error('no idb'); }, deleteDatabase() { throw new Error('no idb'); } };
+global.window = global;
+
+const load = (file, cls) => new Function(fsMod.readFileSync(path.join(ROOT, file), 'utf8') + '\nreturn ' + cls + ';')();
+const VFS = load('virtual-fs.js', 'VirtualFileSystem');
+const AI = load('module-aiassist.js', 'WebX11AIAssistantModule');
+
+function mk() {
+    const out = [];
+    const vfs = new VFS();
+    vfs.saveToStorage = () => true;
+    // Bypass the constructor (it touches the DOM) but keep the real prototype methods.
+    const ai = Object.create(AI.prototype);
+    ai.terminal = { print: (m, t) => out.push({ text: String(m), type: t || '' }), log: () => {}, fs: vfs };
+    ai.checkGuardrail = () => null;
+    return { ai, vfs, out };
+}
+
+let fails = 0, passes = 0;
+function ok(name, cond, detail) {
+    if (cond) { passes++; return; }
+    fails++;
+    console.log('FAIL ' + name + (detail ? ' — ' + detail : ''));
+}
+const run = async (ai, name, args) => JSON.parse(await ai.runTool(name, args));
+
+(async () => {
+    // A. list_files on the virtual /sys mount
+    {
+        const { ai } = mk();
+        const res = await run(ai, 'list_files', { path: '/sys' });
+        ok('A1 /sys lists entries instead of an error', Array.isArray(res), JSON.stringify(res).slice(0, 120));
+        ok('A2 /sys contains the modules mount', Array.isArray(res) && res.some(e => e.name === 'modules'),
+            JSON.stringify(res).slice(0, 160));
+    }
+
+    // B. a genuinely missing directory still reports the error
+    {
+        const { ai } = mk();
+        const res = await run(ai, 'list_files', { path: '/no-such-dir' });
+        ok('B1 missing path reports Directory not found', !!res.error && /Directory not found/.test(res.error), JSON.stringify(res));
+    }
+
+    // C. write_file into a missing parent must not claim success
+    {
+        const { ai, vfs } = mk();
+        const res = await ai.runTool('write_file', { path: '/missing/dir/f.txt', content: 'x' });
+        ok('C1 refused write reports failure', typeof res === 'string' && /Write FAILED/.test(res), String(res));
+        ok('C2 nothing was created', vfs.readFile('/missing/dir/f.txt') === null);
+    }
+
+    // D. the same write succeeds once the parent exists
+    {
+        const { ai, vfs } = mk();
+        vfs.mkdirRecursive('/missing/dir');
+        const res = await ai.runTool('write_file', { path: '/missing/dir/f.txt', content: 'x' });
+        ok('D1 successful write still reports success', /File written/.test(String(res)), String(res));
+        ok('D2 content landed', vfs.readFile('/missing/dir/f.txt') === 'x');
+    }
+
+    if (fails === 0) {
+        console.log('test-ai-fs-tools: ' + passes + ' passed, 0 failed');
+    } else {
+        console.log('test-ai-fs-tools: ' + passes + ' passed, ' + fails + ' FAILED');
+        process.exit(1);
+    }
+})();
diff --git a/modules/test/test-ollama-autoconnect.js b/modules/test/test-ollama-autoconnect.js
new file mode 100644
index 0000000..b9db4ff
--- /dev/null
+++ b/modules/test/test-ollama-autoconnect.js
@@ -0,0 +1,98 @@
+// modules/test/test-ollama-autoconnect.js — run: node
+// Proves the first message lazily connects instead of dying with "Use ollamaconnect first",
+// and that a genuinely unreachable endpoint still produces the error (after one attempt).
+const fsMod = require('fs'), path = require('path');
+const ROOT = path.join(__dirname, '..', 'core');
+const store = {};
+global.localStorage = {
+    getItem: k => (k in store ? store[k] : null),
+    setItem: (k, v) => { store[k] = String(v); },
+    removeItem: k => { delete store[k]; },
+};
+global.window = { addEventListener: () => {}, location: { origin: 'https://webx11.duckdns.org' } };
+global.document = { addEventListener: () => {} };
+
+const OllamaManager = new Function(
+    fsMod.readFileSync(path.join(ROOT, 'ollama-manager.js'), 'utf8') + '\nreturn OllamaManager;')();
+
+let fails = 0, passes = 0;
+function ok(name, cond, detail) {
+    if (cond) { passes++; return; }
+    fails++;
+    console.log('FAIL ' + name + (detail ? ' — ' + detail : ''));
+}
+
+function mk(behaviour) {
+    const out = [];
+    const term = {
+        print: (m, t) => out.push({ text: String(m), type: t || '' }),
+        log: () => {},
+        // chat() prints the model answer through this, even in non-streaming mode
+        printStreamingResponse: (t) => out.push({ text: String(t), type: 'stream' }),
+    };
+    const om = Object.create(OllamaManager.prototype);
+    Object.assign(om, {
+        terminal: term, connected: false, models: [], currentModel: 'm1',
+        endpoint: 'https://webx11.duckdns.org/ollama', fallbackEndpoints: [],
+        providers: [{ name: 'Ollama', type: 'ollama', endpoint: 'https://webx11.duckdns.org/ollama', model: 'm1', priority: 1, enabled: true }],
+        currentProvider: null, fallbackCount: 0, responseHooks: [], _usageLog: [], _usageBuffer: [],
+        _abortController: null, _connecting: null,
+        saveSettings: () => {}, _saveProviders: () => {}, _logUsage: () => {}, _flushUsageLog: () => {},
+    });
+    om.currentProvider = om.providers[0];
+    global.fetch = behaviour;
+    return { om, out };
+}
+
+const json = (body, okFlag = true) => Promise.resolve({ ok: okFlag, status: okFlag ? 200 : 500, json: async () => body });
+
+(async () => {
+    // A. healthy endpoint: the first chat() call connects, then answers
+    {
+        const seen = [];
+        const { om, out } = mk((url) => {
+            seen.push(url);
+            if (url.includes('/api/tags')) return json({ models: [{ name: 'm1' }] });
+            // chat() goes through /api/generate for ollama providers
+            return json({ response: 'pong', message: { content: 'pong' }, eval_count: 1, prompt_eval_count: 1 });
+        });
+        const res = await om.chat('ping');
+        const text = out.map(o => o.text).join(' | ');
+        ok('A1 connect is attempted lazily', seen.some(u => u.includes('/api/tags')), seen.join(', '));
+        ok('A2 the user sees a connecting hint', /Connecting to Ollama/.test(text), text.slice(0, 160));
+        ok('A3 manager is connected after the attempt', om.connected === true);
+        ok('A4 the message is answered', String(res).includes('pong'), String(res).slice(0, 120));
+        ok('A5 no "ollamaconnect first" error', !/ollamaconnect first/.test(text), text.slice(0, 200));
+    }
+
+    // B. dead endpoint: one attempt, then an actionable error
+    {
+        const seen = [];
+        const { om, out } = mk((url) => { seen.push(url); return Promise.reject(new TypeError('Failed to fetch')); });
+        const res = await om.chat('ping');
+        const text = out.map(o => o.text).join(' | ');
+        ok('B1 still attempts the connection', seen.some(u => u.includes('/api/tags')), seen.join(', '));
+        ok('B2 returns null', res === null, String(res));
+        ok('B3 error names the real cause', /endpoint is unreachable/.test(text), text.slice(0, 240));
+        ok('B4 auto-connect failure is reported once', /Auto-connect failed/.test(text), text.slice(0, 240));
+        ok('B5 manager stays disconnected', om.connected === false);
+    }
+
+    // C. concurrent callers share one attempt
+    {
+        let tagCalls = 0;
+        const { om } = mk((url) => {
+            if (url.includes('/api/tags')) { tagCalls++; return json({ models: [{ name: 'm1' }] }); }
+            return json({ response: 'ok', message: { content: 'ok' }, eval_count: 1, prompt_eval_count: 1 });
+        });
+        await Promise.all([om.chat('a'), om.chat('b'), om.chat('c')]);
+        ok('C1 three concurrent messages probe /api/tags once', tagCalls === 1, 'tagCalls=' + tagCalls);
+    }
+
+    if (fails === 0) {
+        console.log('test-ollama-autoconnect: ' + passes + ' passed, 0 failed');
+    } else {
+        console.log('test-ollama-autoconnect: ' + passes + ' passed, ' + fails + ' FAILED');
+        process.exit(1);
+    }
+})();