agent terminal: multi-line textarea input

swap the single-line <input> for an auto-growing <textarea>. enter
submits, shift+enter newlines, ime composition respected (skip submit
while isComposing). height caps at ~12em then scrolls. submit-hint
updates to '↵ send · ⇧↵ newline'. async-form handler now also clears
textareas on success.

hive-ag3nt/assets/agent.css

@@ -156,18 +156,21 @@ pre.diff {
 .term-input { padding: 0.4em 1em 0.8em; }
 .term-input .sendform-term {
   display: flex;
-  align-items: center;
+  align-items: flex-start;
   gap: 0.5em;
   border-top: 1px dashed var(--purple-dim);
   padding-top: 0.5em;
 }
+.term-input .prompt, .term-input .submit-hint {
+  padding-top: 0.25em;
+}
 .term-input .prompt {
   color: var(--green);
   text-shadow: 0 0 6px rgba(166, 227, 161, 0.6);
   user-select: none;
   flex: 0 0 auto;
 }
-.term-input input {
+.term-input textarea {
   flex: 1;
   background: transparent;
   border: 0;
@@ -177,11 +180,15 @@ pre.diff {
   font-size: 1em;
   padding: 0.2em 0;
   caret-color: var(--green);
+  resize: none;
+  overflow-y: auto;
+  line-height: 1.4;
+  min-height: 1.4em;
 }
-.term-input input::placeholder { color: var(--muted); }
+.term-input textarea::placeholder { color: var(--muted); }
 .term-input .submit-hint { color: var(--muted); font-size: 0.8em; flex: 0 0 auto; }
 .term-input.disabled .prompt { color: var(--muted); text-shadow: none; }
-.term-input.disabled input { color: var(--muted); }
+.term-input.disabled textarea { color: var(--muted); }
 .live {
   background: rgba(255, 255, 255, 0.02);
   border: 1px solid var(--purple-dim);

hive-ag3nt/assets/app.js

@@ -47,7 +47,7 @@
         return;
       }
       // Clear text inputs the operator typed into (the form value was sent).
-      f.querySelectorAll('input[type="text"], input:not([type])').forEach((i) => { i.value = ''; });
+      f.querySelectorAll('input[type="text"], input:not([type]), textarea').forEach((i) => { i.value = ''; });
       // Re-enable the button — refreshState() often skips re-rendering the
       // form (status unchanged), so without this the spinner sticks and
       // the operator can't submit again.
@@ -165,20 +165,37 @@
         action: '/send', method: 'POST',
         class: 'sendform-term', 'data-async': '',
       });
+      const ta = el('textarea', {
+        name: 'body', placeholder: 'message ' + label + '…',
+        required: '', autocomplete: 'off', rows: '1',
+      });
+      // Enter submits, Shift+Enter inserts a newline. Auto-grow up to
+      // ~8 rows of content, then scroll inside the textarea.
+      const MAX_PX = 12 * 16; // ~8 lines @ 1.5 line-height, 1em base
+      const grow = () => {
+        ta.style.height = 'auto';
+        ta.style.height = Math.min(ta.scrollHeight, MAX_PX) + 'px';
+      };
+      ta.addEventListener('input', grow);
+      ta.addEventListener('keydown', (e) => {
+        if (e.key === 'Enter' && !e.shiftKey && !e.isComposing) {
+          e.preventDefault();
+          if (ta.value.trim()) form.requestSubmit();
+        }
+      });
+      // Reset height after async submit clears the value.
+      form.addEventListener('submit', () => setTimeout(grow, 0));
       form.append(
         el('span', { class: 'prompt' }, 'operator@' + label + ' ▸'),
-        el('input', {
+        ta,
-          name: 'body', placeholder: 'message ' + label + '…',
+        el('span', { class: 'submit-hint' }, '↵ send · ⇧↵ newline'),
-          required: '', autocomplete: 'off',
-        }),
-        el('span', { class: 'submit-hint' }, 'enter ↵'),
       );
       slot.append(form);
       termInputRendered = true;
     }
     slot.classList.toggle('disabled', !online);
-    const input = slot.querySelector('input');
+    const ta = slot.querySelector('textarea');
-    if (input) input.disabled = !online;
+    if (ta) ta.disabled = !online;
   }
 
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