copy: the thinking-field placeholders, the brief round (release polish 5)

Four placeholders rewritten per the owner's set (2026-10-07): the
thinking fields are an invitation to stream-of-consciousness transfer,
and everything else is implied by the field's existence — no "the
teacher reads all of this", no mechanism, no em dashes, nothing that
wraps. The reading field's placeholder no longer breaks to a second
line.

  quiz:     "Why this answer? Whatever comes to mind."
  reading:  "Whatever comes to mind as you read."
  practice: "Work here, think out loud."
  pause:    "Ask anything, or press Enter for the next one."

The answer-field placeholders ("Type your answer…") stay: brief and
functional already (owner ruling). Quiz placeholder pin updated.

1428 tests, tsc, lint, build green.

components/chat.tsx

@@ -1574,7 +1574,7 @@ export function Chat({
 							// applies.
 							nextProblem={nextReady}
 							onNext={sendNext}
-							placeholder={nextReady ? "Ask about this problem — or press Enter for the next one…" : undefined}
+							placeholder={nextReady ? "Ask anything, or press Enter for the next one." : undefined}
 						/>
 					}
 					onSubmitAnswer={(output) => {

components/practice-dock.tsx

@@ -143,7 +143,7 @@ export function PracticeDock({ problemCallId, input, expanded, onExpand, onSubmi
 							submit();
 						}
 					}}
-					placeholder="Work here — say as much of your thinking as you have."
+					placeholder="Work here, think out loud."
 					rows={4}
 					className={cn(
 						"field-sizing-content lh-input max-h-64 min-h-16 w-full resize-none bg-transparent px-2.5 pb-2 outline-none placeholder:text-muted-foreground",

components/question-dock.tsx

@@ -853,7 +853,7 @@ function QuestionDockForm({
 									submit();
 								}
 							}}
-							placeholder="Why this answer? What are you unsure about? Say as much as you like — the teacher reads all of this."
+							placeholder="Why this answer? Whatever comes to mind."
 							rows={1}
 							className={cn(
 								"field-sizing-content lh-input max-h-48 w-full resize-none bg-transparent px-2.5 py-2 outline-none placeholder:text-muted-foreground/70",

components/reading-thinking.tsx

@@ -85,7 +85,7 @@ export function ReadingThinkingField({
 						e.currentTarget.blur();
 					}
 				}}
-				placeholder="What are you thinking as you read? Say as much as you like — it rides your next check answer to the teacher."
+				placeholder="Whatever comes to mind as you read."
 				rows={1}
 				className="field-sizing-content lh-input max-h-40 w-full resize-none bg-transparent outline-none placeholder:text-muted-foreground/70"
 			/>

tests/render-cards.test.tsx

@@ -143,7 +143,7 @@ describe("render smoke tests", () => {
 		// INSIDE the dock — never called optional, inviting the dump.
 		assert.ok(html.includes('data-testid="thinking-field"'), "thinking field present");
 		assert.match(html, /YOUR THINKING/, "labeled as the learner's voice (all caps, owner round 3)");
-		assert.match(html, /Why this answer\? What are you unsure about\?/, "placeholder invites, not apologizes");
+		assert.match(html, /Why this answer\? Whatever comes to mind/, "placeholder invites, not apologizes (owner, placeholder round 2026-10-07)");
 		assert.ok(!html.includes("optional"), "the field is never called optional");
 		assert.match(html, /Submit answer/, "send becomes Submit answer");
 		assert.match(html, /↵ submits · ⇧↵ newline/, "the standard chord is discoverable (owner round 5)");