test(web): settle the remaining e2e drive gaps

Every consecutive composer send waits out the submit round-trip's
read-only span; the end-of-document caret gesture becomes select-all +
ArrowRight (Cmd/Ctrl+End moves no caret in mac contenteditable), which
lets Lexical's own ancestor scroll walk prove the typing reveal.

apps/web/tests/composer-draft-scroll.e2e.ts

@@ -251,9 +251,12 @@ describe('web e2e: composer draft scrolling', () => {
     onTestFailed(() => saveFailureShot(page, 'web-e2e-composer-draft-scroll-typing'))
     const input = surface(page)
     // Put the caret at the very end, scroll the view away from it, then type:
-    // the browser's own caret reveal must bring the end back on screen.
+    // the editor's own caret reveal must bring the end back on screen.
+    // Select-all + ArrowRight lands the caret at the document end on every
+    // platform (Cmd/Ctrl+End is not a caret move in mac contenteditable).
     await input.click()
-    await page.keyboard.press('ControlOrMeta+End')
+    await page.keyboard.press('ControlOrMeta+KeyA')
+    await page.keyboard.press('ArrowRight')
     await input.hover()
     await page.mouse.wheel(0, -2000)
     await expect.poll(async () => (await measureComposer(page)).scrollTop, { timeout: 10_000 }).toBe(0)

apps/web/tests/queue-actions.e2e.ts

@@ -217,6 +217,8 @@ describe('web e2e: queue row actions', () => {
     await page.locator('[data-testid="todo-panel"]').waitFor({ timeout: 10_000 })
 
     for (const text of ['Layout queue first', 'Layout queue second']) {
+      // A just-submitted composer is read-only for the prompt round-trip.
+      await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
       await input.fill(text)
       await input.press('Enter')
     }

apps/web/tests/steering.e2e.ts

@@ -99,11 +99,13 @@ describe('web e2e: mid-turn steering lands durably and visibly', () => {
     const input = page.locator('[data-composer-input]').first()
     await input.waitFor({ timeout: 10_000 })
     const settled = scaffold.whenTurnSettled(MODE === 'record' ? 180_000 : 30_000)
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(PROMPT)
     await input.press('Enter')
 
     // Enter remains the Queue gesture. The row action then atomically moves
     // this exact occurrence into the current turn's steering outbox.
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(STEER)
     await input.press('Enter')
     const queuedRow = page.getByRole('listitem').filter({ hasText: STEER })
@@ -203,10 +205,12 @@ describe('web e2e: composer shortcut steers directly', () => {
     const input = page.locator('[data-composer-input]').first()
     await input.waitFor({ timeout: 10_000 })
     const settled = scaffold.whenTurnSettled(30_000)
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(PROMPT)
     await input.press('Enter')
     await page.getByRole('button', { name: 'Stop generating' }).waitFor({ timeout: 10_000 })
 
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(STEER)
     await input.press('Meta+Enter')
     await expect.poll(() => input.textContent(), { timeout: 5_000 }).toBe('')
@@ -265,11 +269,13 @@ describe('web e2e: composer shortcut follows the swapped busy behavior', () => {
 
     const input = page.locator('[data-composer-input]').first()
     const settled = scaffold.whenTurnSettled(30_000)
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(PROMPT)
     await input.press('Enter')
     await page.getByRole('button', { name: 'Stop generating' }).waitFor({ timeout: 10_000 })
 
     const queuedText = 'Queued by the complementary Cmd+Enter shortcut.'
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(queuedText)
     await input.press('Meta+Enter')
     const queuedRow = page.locator('[data-queue-dock]').getByRole('listitem').filter({ hasText: queuedText })
@@ -329,10 +335,13 @@ describe('web e2e: empty-draft Cmd+Enter steers the whole queue', () => {
 
     // Call 0 streams a question-tool call; the fills must land inside the
     // first replay window, before the question composer replaces the textarea.
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(PROMPT)
     await input.press('Enter')
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(STEER_ONE)
     await input.press('Enter')
+    await page.locator('[data-composer-input][contenteditable="true"]').first().waitFor({ timeout: 10_000 })
     await input.fill(STEER_TWO)
     await input.press('Enter')
     const dock = page.locator('[data-queue-dock]')