[barelyworkingcode]

Closes #541

fakerelay now serves the adopt fields on outside rows (adoptable, adoptReason, a live row's claudeSessionId). It also answers POST /api/sessions/adopt with relay's success shape and every refusal code and message, word for word. A test chooses the outcome through the world's adopt object, and existing fixtures load unchanged: rows with no keys read adoptable:false, with the reason derived in relay's order.

• The merged relay code wins over relay#527's contract in five places. The issue's contract lists them.
• The rule that refused a live row's claude_session_id is lifted, because relay#527 now serves that id on live rows. Two assertions in outside_test.go changed. Bad values stay refused on live and ended rows.
• No docs/FEATURES.md row moves. fakerelay/** and e2e/contract/** are in the no-test area, and nothing a user reaches changed.
• Waits: the instance ready line, HTTP answers, until on WebSocket revisions, and a followed log for session.adopt. No sleeps.

Tests: fakerelay/prooftest/adopt_test.go (row fields, fixture rules, success, interrupt and recovery, all refusals, door class) and e2e/contract/s_adopt_test.go (the refusals both targets can stage; their transcripts match).

Runs on dc0aaf8:

• (cd fakerelay && go test -race -count=1 ./...): ok.
• TestAdoptContractRefusals: ok on both targets.
• The full e2e/contract: two older tests are red, and they are red on the epic base too (552a068). The cause is relay#559, filed: the epic's real relay answers providerState on POST /api/sessions. main is green.
• e2e feature baseline: one load flake, TestRefusedSecondMessageKeepsFirstReply, green three times alone. This PR does not touch relay itself.

Fix attempts: one review fix round (message assertions and the ambiguous staging), then one line for launch_failed. Tokens: about 0.75M across subagents.

Minor, not fixed (theoretical): an adopted fake session records its conversation id just after it joins the list, and launch_failed answers even if a fixture replace already dropped the row.

Review: no blocking findings (round 3, clean)
Journey: n/a: fakerelay is a test tool; no devbox journey reaches it
Break-and-restore: serving adoptable as false turned TestAdoptRowFieldsServed red; a changed launch_failed message turned TestAdoptRefusals red; both restored byte for byte
Weakening reviewed: outside_test.go live-row claude_session_id refusal lifted; relay#527 decision 2 serves the id on live rows; bad-value refusals kept

🤖 Generated with Claude Code

[barelyworkingcode]

merge-check: merged. approved, target, contract, evidence, owner, weakening