feat(boatstack): goal escapes — the merged pursuit is bounded and demotes

[bigboateng]

Sixth slice of the published → merged program (follows #240). Autonomy arrives pre-bounded: the merged-terminal pursuit runs only inside an explicit contract, and any disturbance that ends the contract demotes the step to the operator and stops.

What changed

• The contract: at most 3 recorded post-publish fix cycles (PostPublishFixAttempts, an offline counter on the published slice mirroring RepairAttempt < 3), no changes-requested review verdict, and a cleanly merging branch (DIRTY fires base_conflicts; BEHIND deliberately does not — it is often auto-resolvable and already lands on an operator-owned Unknown phase without stickiness).
• The demotion: a fired escape makes classifyNextActor return operator unconditionally, prescribePostPublish return nothing (demote-and-stop, never demote-and-suggest), the status reason explain the pause, flow watch treat it as a frontier change, and the frontier row carry it.
• Sticky offline: the fired escape is cached best-effort on the slice — the same bounded modeled bypass as the terminal PRState cache; the delivery.next registry note now names it. A fresh session with gh unavailable still demotes. A perfect-looking live observation cannot re-arm an escaped pursuit.
• The reset: recording the next correction (record-change) clears the escape and restarts the cycle at one — the explicit operator-authorized act, consistent with the protocol's frontier rules.
• Default untouched: under published, no escape is ever evaluated, surfaced, or written; state files stay byte-stable through correction cycles (pinned).

Boundary conformance

• Boundary: autonomous pursuit authority meeting its limits.
• Control law: goal-escape-demotes-to-operator-and-stops.
• Required evidence: goal_escape_conformance_test.go — positive (each live disturbance → operator + nothing prescribed + explanatory reason), relation (budget exhausts offline with gh down; persisted escape sticky; recorded correction resets to cycle 1), negative (unspent budget keeps prescribing; published default writes zero bookkeeping), bypass (escaped delivery never gets the merge prescribed again — even under a live merge-eligible observation — until the recorded reset).
• Failure behavior: fail-closed to operator; escape evaluation is pure and offline-first.
• Release condition: full suite green; additive omitempty fields only, no schema bump.

Evidence

• go build ./... && go vet ./... && go test ./... — pass.
• Release note added: 2026-07-28-bounded-merge-pursuit.md.

Next: the offline retro miner (recurrence detection over transcripts → typed proposals).