refactor(*): the dag card hands its graph to the desk task pane

[0xKT]

Summary

The orchestration card in the transcript (a run_subagent_dag or load_playbook
row, expanded) drew a graph of its own and, under it, a node panel whose "open the
run" link raised the old agents-panel record window. The desk's task pane already
draws the same graph and reads the same dag.node record, node by node, so the
card was a second renderer for work the desk owns. The prototype's card is the grid
alone, with the task cell as the door to the run. This PR makes the card that.

Two commits, the second deleting only what the first killed:

1. The card hands its graph to the desk. The card keeps its grid (task, scale,
   playbook, state, cost, run id, replanned-into) and nothing else. The task cell is
   a door -- role=button, a title, a standing arrow -- whenever the run has an
   id, and opens the run's task pane on the desk. openDagRun goes through the
   tasks seam: openRun when the tasks store holds the row, one tasks.list read
   when it does not, the tasks tab when neither answers (a branched conversation
   replaying its parent's delivered row lands there). The delivered row already
   went through openDagRun and follows. The node panel, the openDagNode seam,
   features/dag/open.ts, the 21 catalogue keys only the panel read and the
   dag-renderer gate go.
2. The renderer's default box goes. The desk's board is DagGraph's only
   caller and hands it its own node card, so the default SVG box, the card
   surface, the label trimming, the mark table and the per-node clock had no
   reader left.

User-visible changes besides the door: the first failed node is no longer opened
unasked inside the card (the desk pane's failure banner names it, one click away);
a node's internal dependencies are read off the board's edges rather than a list;
the node id, which the deleted panel spelled out, rides on the desk node panel's
title.

Left for a follow-up, deliberately: features/dag/mount.ts and store.ts (the run
state state/session/resume.ts still writes and nothing reads) -- deleting them
means either a new row on domain-shape's shrink-only exceptions or dissolving
features/dag/ into its two remaining consumers, which is a decision of its own.

Type

• Fix
• Feature
• Docs
• CI / tooling
• Refactor
• Other

Verification

• npm test --prefix ui-web -- 188 files, 2464 tests, all pass (three suites
  fewer than the base: the two deleted gates and the deleted label suite)
• npm run type-check --prefix ui-web -- clean
• npm run lint --prefix ui-web -- 0 errors (4 pre-existing warnings in
  CronPage/SubagentsPage, untouched here)
• node ui-web/scripts/check-class-namespace.mjs -- OK; the transcript and dag
  pins lowered to what the tool prints
• npm run --prefix ui-tui lint:i18n -- generated catalogue up to date
• npm run --prefix ui-web build && python3 ui-web/build.py -- boot-snapshot OK
  (235 nodes match golden)

Driven on a real host (raven serve from this branch on an isolated RAVEN_HOME
built from a real config, deepseek as the default model, every channel off), with
a playwright driver against the served page:

Step	Result
Expand the card of a running three-node graph	grid only, no graph, no node panel; task cell is role=button with a title and the arrow; a long title is cut and the arrow stays in view
Click the task cell	exactly one desk pane, task:dag:<run_id>, headed by the run's summary, showing the board
Click a node on the board	the desk's node panel with the node's record
Click the task cell again	no second pane
Click the delivered row after the run settles	the same pane
Reload, expand the restored card, click	the same pane
A graph with one node on a lane that cannot reach its model	the card's state row counts 1 failed; the desk pane shows the failure banner before any node is picked; the banner opens the failed node
The board before and after commit 2	screenshots identical (node cards, edges, lane frames)

• Relevant tests pass locally
• Relevant lint / type checks pass locally
• User-facing docs or screenshots are updated when needed

Risk

Web UI only; no server or wire change. The transcript card loses its graph and
node panel on purpose; every fact they showed is on the desk's task pane, reached
from the card's task cell and from the delivered row. features/dag/mount.ts keeps
running unchanged. Rollback is reverting the squash commit.

• Security impact considered
• Backward compatibility considered
• Rollback path is clear for risky changes

Related Issues

N/A

[gloryfromca]

No blockers; suggestions only, and they are marked inline.

The refactor has one task renderer after the transcript card hands off through the tasks seam, and the removed DAG renderer surface, CSS, catalogue keys, and tests have no remaining callers. The new summary/door behavior and the narrowed caller-supplied DagGraph contract are covered well.

I checked AGENTS.md/CLAUDE.md and the Web UI context, the full diff, surrounding callers, commit history, compatibility of the removed exports and i18n keys, and that the tests were replaced with state/door assertions rather than merely weakened. I found one nonblocking stale-response race in the fallback opener, marked inline.

Verification: npm test (188 files, 2,464 tests passed); npm run type-check (passed); npm run lint (passed with four existing hook warnings in untouched files). git diff --check passed.