feat: AI Assistant at the top of the main menu; warn-only conversation budget

public/components/assistant.html

@@ -65,8 +65,7 @@
 
               <form id="assistant-form" class="assistant-composer">
                 <label for="assistant-input">Clinical question</label>
-                <textarea id="assistant-input" rows="1" placeholder="Ask a focused clinical question..." autocomplete="off" aria-describedby="assistant-context-budget assistant-context-warning"></textarea>
-                <p id="assistant-context-budget" class="assistant-muted" aria-live="polite">Loading conversation limit; history and draft are counted in UTF-16 code units. The server validates each request.</p>
+                <textarea id="assistant-input" rows="1" placeholder="Ask a focused clinical question..." autocomplete="off" aria-describedby="assistant-context-warning"></textarea>
                 <div id="assistant-context-warning" role="alert" hidden></div>
                 <div id="assistant-attachments" class="assistant-attachments" aria-label="Attached images" hidden></div>
                 <div class="assistant-composer-footer">

public/index.html

@@ -211,6 +211,10 @@
         </button>
       </div>
       <div class="sidebar-nav">
+        <button class="tab-btn" data-tab="assistant">
+          <i class="fas fa-brain" style="color:var(--purple);"></i>
+          <span>AI Assistant</span>
+        </button>
         <span class="sidebar-section-label">Encounters</span>
         <button class="tab-btn active" data-tab="encounter">
           <i class="fas fa-comments"></i>
@@ -278,10 +282,6 @@
           <i class="fas fa-diagram-project"></i>
           <span>Diagrams</span>
         </button>
-        <button class="tab-btn" data-tab="assistant">
-          <i class="fas fa-brain" style="color:var(--purple);"></i>
-          <span>AI Assistant</span>
-        </button>
         <button class="tab-btn hidden" data-tab="cms" id="cms-tab-btn">
           <i class="fas fa-pen-to-square"></i>
           <span>Content Manager</span>

test/assistant-image-attachments.test.js

@@ -363,9 +363,7 @@ test('UI sends images only with the question, clears them on success, persists t
   const input = ui.document.getElementById('assistant-input');
   input.value = 'x';
   input.dispatchEvent(new ui.dom.window.Event('input'));
-  const label = ui.document.getElementById('assistant-context-budget');
-  assert.equal(label.textContent, '1,000 / 1,000 conversation characters (UTF-16 code units).', 'budget label stays text-only');
-  assert.doesNotMatch(label.textContent, /image/i);
+  assert.equal(ui.document.getElementById('assistant-context-budget'), null, 'the constant character counter is gone; only the approaching-limit warning remains');
 
   // Pending attachments stay input-only until the question is sent.
   ui.context.performAutosave();

test/frontend-prompt-env.test.js

@@ -204,8 +204,8 @@ test('native conversation UI counts UTF-16 history + draft, warns at exactly 90%
   });
   await loadChat(ui);
   const warning = ui.document.getElementById('assistant-context-warning');
-  const usage = ui.document.getElementById('assistant-context-budget');
-  enter(ui, ''); assert.match(usage.textContent, /899 \/ 1,000.*UTF-16 code units/); assert.equal(warning.hidden, true);
+  assert.equal(ui.document.getElementById('assistant-context-budget'), null, 'no constant counter — warnings only');
+  enter(ui, ''); assert.equal(warning.hidden, true);
   enter(ui, 'x'); assert.equal(warning.hidden, false); assert.match(warning.textContent, /90%/);
   enter(ui, 'x'.repeat(101)); assert.match(warning.textContent, /At the conversation limit/);
   const input = enter(ui, 'x'.repeat(102));
@@ -266,12 +266,10 @@ test('missing/invalid metadata never fabricates a cap; authoritative refusal kee
         if (url.endsWith('/chat/stream')) return json({ error: 'Environment budget refused', budget: { limit: 1000 }, code: 'CONVERSATION_LIMIT' }, 413);
       });
       enter(ui, '😀'.repeat(501));
-      assert.match(ui.document.getElementById('assistant-context-budget').textContent, /1,002.*Limit unavailable/);
-      assert.doesNotMatch(ui.document.getElementById('assistant-context-budget').textContent, /120,000/);
+      assert.equal(ui.document.getElementById('assistant-context-budget'), null, 'no fabricated counter when the limit is unavailable');
       await ask(ui);
       assert.equal(ui.document.getElementById('assistant-input').value, '😀'.repeat(501));
       assert.equal(ui.document.querySelectorAll('.assistant-msg').length, 0);
-      assert.match(ui.document.getElementById('assistant-context-budget').textContent, /1,002 \/ 1,000/);
       assert.match(ui.document.getElementById('assistant-context-warning').textContent, /Sending is blocked/);
       await ask(ui);
       assert.equal(ui.calls.filter(c => c.url.endsWith('/chat/stream')).length, 1, 'subsequent refusal is local');