fix(web): separate transcript scrolling from composer

web/src/structured.test.ts

@@ -1227,6 +1227,18 @@ describe("structured connection: transcript scrolling", () => {
 describe("structured connection: pane lifecycle", () => {
   beforeEach(() => vi.clearAllMocks());
 
+  it("keeps the composer outside the transcript scroll region", () => {
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const main = conn.el.querySelector(".structured-main")!;
+    const scroll = conn.el.querySelector(".structured-scroll")!;
+    const composer = conn.el.querySelector(".structured-composer")!;
+
+    expect(main.contains(scroll)).toBe(true);
+    expect(main.contains(composer)).toBe(true);
+    expect(scroll.contains(composer)).toBe(false);
+    conn.dispose();
+  });
+
   it("sendInput is a no-op — there is no PTY behind a structured session", () => {
     const conn = mount({ sockets: [new FakeSocket()] });
     expect(() => conn.sendInput("\x0b")).not.toThrow();

web/src/structured.ts

@@ -65,8 +65,10 @@ export function createStructuredConnection(
       <button class="btn btn-ghost btn-icon disconnect" type="button" aria-label="Disconnect" title="Disconnect this session">⏻</button>
     </header>
     <div class="structured-body">
-      <div class="structured-scroll">
-        <div class="structured-rows"></div>
+      <div class="structured-main">
+        <div class="structured-scroll">
+          <div class="structured-rows"></div>
+        </div>
         <form class="structured-composer">
           <textarea class="structured-input" rows="1" placeholder="Reply, or / for commands…"></textarea>
           <button type="submit" class="btn btn-primary structured-send">Send</button>

web/src/styles.css

@@ -2193,7 +2193,7 @@ input.leaf-rename:focus {
   grid-template-rows: auto minmax(0, 1fr);
 }
 
-.structured-body.st-narrow .structured-scroll {
+.structured-body.st-narrow .structured-main {
   grid-row: 2;
 }
 
@@ -2204,16 +2204,22 @@ input.leaf-rename:focus {
   max-height: 40%;
 }
 
-.structured-scroll {
+.structured-main {
   min-width: 0;
-  overflow-y: auto;
+  min-height: 0;
   display: flex;
   flex-direction: column;
 }
 
+.structured-scroll {
+  flex: 1 1 auto;
+  min-height: 0;
+  min-width: 0;
+  overflow-y: auto;
+}
+
 .structured-rows {
-  flex: 1 0 auto;
-  padding: var(--sp-3) var(--sp-3) 0;
+  padding: var(--sp-3);
   display: flex;
   flex-direction: column;
   gap: var(--sp-3);
@@ -2616,11 +2622,10 @@ input.leaf-rename:focus {
   border-color: var(--danger);
 }
 
-/* composer: sticky at the bottom of the scrolling transcript column */
+/* The composer is a sibling of the scrolling transcript, not part of it: it
+   stays reachable at the pane edge without changing transcript scroll math. */
 .structured-composer {
-  position: sticky;
-  bottom: 0;
-  margin-top: var(--sp-3);
+  flex: 0 0 auto;
   padding: var(--sp-3);
   border-top: 1px solid var(--border);
   background: var(--surface);