fix(dag): complete workflows at rejected review checkpoints instead of failing them

[LeXwDeX]

Closes#294

Summary

A REJECT verdict terminalized the workflow as failed — and failed workflows are immutable. That made two of the four Verdict Disposal Contract options physically unreachable (additive extend reopen requires completed; replan rejects terminal workflows), so post-checkpoint correction waves could never happen. The harness also contradicted its own policy: node-level rule says a REJECT gate is a completed node, while the workflow level failed the graph for it.

The reopen mechanism was explicitly designed for this shape (its rationale names skipped dependents as non-executed, so the graph "effectively ended at the checkpoint") — it was simply unreachable.

Change

• The scheduling loop completes the workflow at an unresolved-review checkpoint instead of failing it; the REJECT shape (skipped dependents, reporting leaf) is exactly what reopen-extend picks up.
• dag.complete gains an explicit skipReviewGate option: explicit completion shortcuts (tool/HTTP) keep the review gate; only the natural loop path passes the bypass.
• workflow(action="status") surfaces unresolved_reviews explicitly instead of burying the verdict in a terminal reason string.

Verification

• Wake-integration expectations rewritten to the new contract (deep + standard modes: REJECT shape settles completed, review/audit nodes skipped, parent woken with the completed terminal wake).
• Explicit-completion rejection tests unchanged and green (dag.complete default still guarded).
• 543 DAG/tool tests green; bun typecheck clean from packages/opencode.

Note

Pairs conceptually with #299 (parallel writers) and the disposal wording in the docs/disposal-classifier branch; independent in code, safe to merge in any order.