#2775 gatorwalk-factory: restart at triage keeping what was recorded (gap 7)

This closes gap 7 in lifecycles/swamp-extensions.md:212-215. #2734 and #2732 put it off.

The difference

• issue-lifecycle: start from any phase puts the lifecycle back at triaging and keeps every resource. The plan, reviews and verification stay readable, and the next triage and plan build on them. It posts triage_started again (extensions/models/issue_lifecycle.ts:914-990). Its status moves are no-ops once the issue is further along (changelog 2026.09.25.1).
• gatorwalk: reset starts a new era. Earlier products, approvals and dispatches stay recorded but "belong to the old era, so no gate sees them" (DESIGN.md:306-308). CEL, bindings and context.inject see nothing from before. No entry is posted for a reset (swamp-extensions.md:148-149).

Why it matters

In the pilot, reset is the only way back from a wrong classification once past reproduce. It throws away the plan and reviews the next pass should build on. The Lab history also shows nothing about the restart.

Fix direction

This may be possible in the YAML with no format change: a global, manual restart to triage behind a human-approval gate, like abandon. It stays in the era, so everything recorded remains visible, and entering triage posts triage_started again.

Decisions for the implementer:

• Cycle limits. Global transitions are exempt from cycle limits (DESIGN.md:302-305, :408-410). They were meant as escape hatches, and restart would make them a loop. Decide whether that is acceptable or whether a non-terminal global target should count against triage's maxCycles. Check what the graph analysis reports for it (escape-only and the count pass).
• Stale era-wide products. CEL evidence[...] reads the latest record in the era from any stage (swamp-extensions.yaml:26-29). Check every CEL gate past implement for one that an old verification or conformance could satisfy after a restart. attest.complete and merge.complete are only reachable after a fresh verify.passed, but show that in a test.
• Reset or restart. If a format change is preferred, it could be reset with a keep option. Say why.

Done when

• A walk test restarts from implement to triage. The earlier plan and review are readable and injected, the next exits still need fresh products this cycle, and no complete exit opens on stale ones.
• validate passes with no new errors.
• Gap 7 is marked resolved, and the Phases table row for start reads "Fits".