fix(prover-node): do not abort in-flight proving jobs on a clean shutdown

[AztecBot]

v5 version of #24562 (based on merge-train/spartan-v5). Stacked on #24578 — review/merge that first.

Note: this is a fresh implementation, not a port — the v5 prover-node architecture differs from next (it uses EpochSession / TopTreeJob rather than EpochProvingJob / ProvingOrchestrator), which is the structure actually running on testnet.

Problem

On a clean shutdown, SessionManager.stop() cancels every live session with reason 'prover-node stopping'. That flows EpochSession.cancel → TopTreeJob.cancel() → topTree.cancel({ abortJobs: true }) — the abortJobs: true was hardcoded, so a deploy/restart aborted the in-flight top-tree broker jobs. Aborting on a clean restart is wasteful: the proofs are still valid, agents are mid-flight, and a restarted node re-orchestrating the same epoch produces the same deterministically-hashed job ids, so it re-proves from scratch.

Fix

Thread an abortJobs decision from the cancel reason down to the broker:

• SessionManager.stop() cancels with { abortJobs: false } — a clean shutdown preserves the jobs.
• EpochSession.cancel(reason, { abortJobs }) forwards it to TopTreeJob.cancel(abortJobs) → topTree.cancel({ abortJobs }).
• All other cancels (reorg / supersede / deadline) keep the default abortJobs: true, since their inputs are stale.

Composes with #24578: a clean redeploy mid-epoch neither cancels the in-flight jobs nor (if one ever were aborted) poisons them, so the epoch keeps proving across the restart.

Tests

• session-manager.test.ts: stop() cancels every session with abortJobs: false.
• epoch-session.test.ts: a normal cancel forwards abortJobs: true to the top-tree orchestrator; a clean-shutdown cancel forwards abortJobs: false.

Note: not run locally in this session — the prover-node suite needs a full noir/wasm bootstrap that wasn't available here — so relied on CI.

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Created by claudebox · group: slackbot