Remove Morning brief, Needs you, Running and Agents from Today until each is proven #615

User story

As the owner, I want Today to show only parts that work, so that the first screen I see can be trusted while the core product settles.

Acceptance criteria

• Today does not show the Morning brief, Needs you, Running or Agents parts.
• Today still shows the greeting and summary, Ask, Start tiles, Continue, Routines and Projects.
• Nothing else changes: the project page Agents list, the Chief of Staff rail and the permission prompt over every screen still work.
• The four part files stay in the tree and are unregistered in one place (public/home-screen.js), so each can return by re-registering it.
• Every devboxverify journey that reads today-part-agents, today-agent-*, today-agents-group-*, today-drop-in-* or today-part-brief asserts the same behaviour on a surface that still exists.
• brief-injection-refused keeps its security half (relay's gate) and drops its Today half.
• No journey is removed, no timeout widened, no assertion weakened. Each retarget is listed in the PR.
• Feature map rows for the four parts (G1.9 to G1.12, G1.14 to G1.21, G4 agent-board rows, G6 rows that name Today's board) say "not shown on Today" and name the issue that brings each back.
• The hermetic specs for the four parts are skipped with the reason and this issue's number, or retargeted. npm run check:coverage passes.

What I'd notice

Today is shorter: no empty Needs you, Running or Agents blocks, and no Morning brief error.

Context

• The brief shows "The brief came back in a form eve can't read." on the owner's setup. Cause not yet known. Re-adding the brief is a separate issue, to be designed with a journey that proves a readable brief.
• The Morning brief task already in relayScheduler is not touched by this issue. It keeps running daily until the owner disables it.
• Order to re-add, each with its own journey first: Needs you, Running, Agents, Morning brief.
• The brief is all in eve (public/today/brief.js, parts/brief-part.js); the task lives in relayScheduler and is created through eve's /api/tasks. No relay change is needed.

Tasks

• Unregister the four parts in public/home-screen.js.
• Retarget the devboxverify journeys that read the Today agent board to the project page Agents list or the Chief of Staff rail, whichever carries the same proof.
• Drop the Today half of brief-injection-refused.
• Update the feature map and README journey text.
• Skip or retarget the hermetic specs for the four parts.
• Verification task: repo suite, devboxverify on the head, real-app check of Today.

Contract

Ownership (from the coordinator brief, plus the amendment comment of 2026-10-22):

• public/home-screen.js: unregister BriefPart, NeedsYouPart, RunningPart and AgentsPart in one place.
• public/index.html (only if needed).
• devboxverify/: retarget journeys, drop brief-injection-refused's Today half, add today-trimmed; devboxverify/README.md.
• test/e2e/: skip or retarget the hermetic specs.
• test/static/frozen.json: today-trimmed, and the projects area on the retargeted journeys (amendment).
• docs/FEATURES.md, docs/design-today-s1.md, docs/design-brief.md, docs/design-workbench.md.

Waits: journeys wait on session_state frames, the greeting and the board rows; specs wait on visible text.