LlamaCasty/TASKS/task-69-chat-preview-toggle.md

TASK 69 — Chat sample-preview toggle

Status: ☐ Queued (creator request 2026-11-11); scheduled after TASK 68 and before the gold pass.

Request

Expose the autogenerated sample chatter as a per-ChatBox layer-control toggle, so the creator decides whether it appears while adjusting chat font/color and previewing the layout. Keep the existing behavior as the default: Source.ChatPreviewEnabled already defaults to true.

Established behavior

• ChatOverlayLayer.StartMockPreview autogenerates sample messages for the ChatBox preview.
• A real message stops the sample loop; after the real-message fade clears the buffer, the sample loop starts again—even during a live session.
• Samples are preview-only: they are not inserted into the real Messages buffer, and the output renderer reads that real buffer. Viewers do not receive sample chatter.
• ChatPreviewEnabled is currently read by the mock-preview starter but is not persisted.

Acceptance

• The selected ChatBox layer control exposes Show sample chat in preview, on by default.
• The choice persists across restart and applies to that ChatBox layer.
• Off stops/removes generated samples. It does not hide real chat messages or change the live output.
• When on, samples return in the preview when there are no real messages to show.
• One Good Dog integration test covers the toggle and persistence; pin that sample chatter never enters the output message buffer.