[spl-token] test_process_transfer_multisig proof fails with fail_fast

[Stevengre]

Summary

test_process_transfer_multisig proof reports ProofStatus.FAILED when run with --fail-fast option on token_ref=origin/proofs (24f50e88) + mir-semantics 3254f5f7.

This is likely a false positive caused by --fail-fast: the failing node (node 63) is an Endprogram node — it should be a valid terminal state, not a failure. The --fail-fast option appears to prematurely flag this node as failing while 9 pending leaves remain.

Observed behavior

• Command: program/test-properties/run-proofs.sh -c -t 600 -w 4 test_process_transfer_multisig
• Result: ProofStatus.FAILED with pending: 9, failing: 1, stuck: 0, terminal: 10
• The single failing leaf is node 63, which is an Endprogram node
• Subsequent kmir show --statistics --leaves does not show a persisted failing bucket

Root cause hypothesis

The --fail-fast option incorrectly treats the Endprogram node 63 as a failing leaf, causing the proof to report FAILED status prematurely. This is a tooling/option issue, not a semantic failure.

Expected behavior

Node 63 (Endprogram) should be recognized as a valid terminal state. The proof should not report FAILED for an Endprogram node.

Acceptance criteria

1. Confirm that node 63 is indeed an Endprogram node and should be terminal (not failing).
2. Re-run without --fail-fast (or with a fix) and verify ProofStatus.PASSED.
3. Update tracking row in [MAIN] SPL-Token Proof Status #47.

Evidence

• Tracking: [MAIN] SPL-Token Proof Status #47
• Baseline: token 24f50e88, mir-semantics 3254f5f7