chore(mir-semantics): bump submodule for close-account multisig volatile write fix

[Stevengre]

Summary

Bumps p-token/test-properties/mir-semantics to include the singleton-array projection fix for AccountInfo::assign-style write_volatile::<[u8; 32]> writes.

Submodule update:

• fix(rt): normalize singleton-array volatile pubkey writes mir-semantics#984

Why

test_process_close_account_multisig hits a semantic blocker in the delete_account -> AccountInfo::assign -> write_volatile path (singleton-array projection/writeback shape). This bump pulls in the targeted semantics repair plus reproducer coverage.

Testing

Remote execution (zhaoji):

• standalone reproducer pass:
  • uv --project kmir run -- kmir prove-rs ... write_volatile_pubkey_array.rs --start-symbol repro --fail-fast
  • result: PASSED, nodes=3, failing=0, stuck=0
• integration pass:
  • make test-integration TEST_ARGS="-k write_volatile_pubkey_array"
  • result: 1 passed
• top-level proof rerun:
  • program/test-properties/run-proofs.sh -t 7200 -w 1 test_process_close_account_multisig
  • current status: still running (not completed yet); latest sampled proof state shows nodes=28, leaves=9, terminal=1, pending=8, failing=0, stuck=0.

Known out-of-scope issue remains unchanged:

• [spl-token] test_process_thaw_account_multisig: stuck/failing leaf from unconstrained symbolic multisig #181 (uninitialized multisig OOB)