Repair server-read retries and contain resume editor width #40

During the bounded synthetic client-state audit for SaaS Maker #244, two RolePatch defects were reproduced:

• After a server route read failed, Try again called reset, which cleared the boundary but reused the failed server payload. Next.js 16.3.8 supplies retry to refetch and render the segment. The seven existing boundaries need that callback while preserving their current recovery UI and URL/query state.
• The editor's inset flex child retained its intrinsic minimum width, causing page-level horizontal overflow at compact widths. It needs to shrink within the workspace while preserving the 816px resume-paper layout and its existing preview behavior.

Acceptance:

• An actual failed server read is retried, can fail again without fake empty content, and recovers after the fixture becomes available; ?page=2 remains intact.
• All seven boundaries call the framework refetch callback; regression checks pass.
• Editor controls remain usable at 390/768/1440, the document does not overflow horizontally, and the paper remains 816px.
• Preserve established design, existing history and all other workspace work. Run owning-repository checks and responsive headless rendering.

This issue covers the source repair and synthetic local qualification. The broader cold-placeholder timing target, generated/PDF/AI outputs, live identity/provider behavior, native-device/WebKit checks and production release remain separate gates; the parent acceptance stays open.