[lavaman131]

Two fixes: a finished workflow run lost its stages when an attached Planner reattached, and a wide Mermaid diagram on a decision card opened cut off at the card's edge.

A run's stored stages survive a reattach

A Planner that reattaches reports the runs it remembers again. An ended run whose stages it no longer holds arrives as a full card with no stages. That card replaced the run's stages: Chat deleted the stages it had stored and showed a card with none. A finished run's "+N earlier" then unfolded to nothing, even after a reload.

The rule now: a full card with "stages": [] for a run that already has stages keeps them. Its other fields, such as the status and times, still change the card, and its earlierStages is ignored. A full card with any stages still replaces them all, so the contract for clients that send stages is unchanged. docs/agent-connection.md states the rule under Run stage deltas.

• apps/server/src/harness/remote/link.ts: within one agent connection session, an empty full card keeps the session's stages for that run. Delta cards that follow add to them.
• apps/server/src/chat/service.ts: for a report from a later session, Chat keeps the card's stages and leaves the stored ones alone.

Runs whose stages are already gone cannot be restored. Chopin keeps no other record of them:

• Chat's run card holds only the latest 12 stages, and the reattached report overwrote that card.
• The document checkpoint copies the card within half a second of each change.
• Channel events and document versions do not record runs.

No repair task was added. It would have nothing to restore from.

A card's diagram opens fitted to the card

A Mermaid diagram on a decision card opened at its drawn width, so a chart wider than the card was cut off until someone pressed Fit diagram to width. A card's diagram now opens fitted to the card's width, with Actual size to draw it at its own size and scroll it. On a phone the card offers Expand diagram for a full-screen reading. A diagram in the document opens exactly as before.

Verification

• Tests written red first:
  • The link test failed on the old code because an empty full card cleared the session's stages.
  • The Chat test failed because the stored stages went from 16 to 0.
  • The editor unit test failed because the card's diagram rendered without data-fit.
  • Both new browser tests failed because the card's drawing scrolled and was cut off.
• bun test: 6473 passed. bun run types and bun run ci pass, and no design-contract hashes changed.
• Chromium: decision-markdown, wide-content, run-card and planner-attachment all pass (20 tests). The new browser tests check the card at 1280 px and on a 390 px touch phone.
• apps/connector is unchanged.