[scorecard][utf] Support transaction operation adapters in unified runner

[midagedev]

Parent Epic: #98

Why

Top unsupported reason includes unsupported UTF operation: startTransaction (baseline count: 234).
Command-level transaction support exists; unified operation adapter coverage is the likely gap.

Scope

• Implement UTF operation adapter handling for transaction lifecycle operations used by official specs.
• Map adapter outputs to existing command envelope semantics.
• Add focused tests for transaction operation mapping and state transitions in UTF runner context.

Success Criteria

• Unsupported reason startTransaction is reduced to zero or near-zero in rerun artifacts.
• Imported differential case count increases without introducing mismatches.
• Deterministic transaction behavior remains unchanged.

Priority

P1 (immediately after #99 baseline run).

[midagedev]

Progress update after merged PR #105:

• Added transaction operation adapters in UTF importer (startTransaction / commitTransaction / abortTransaction) with session envelope injection.
• Local rerun shows transactions-unified imported coverage increased from 0 to 162.
• Unsupported total in transactions-unified dropped from 396 to 228.

Current status: kept OPEN.

• Remaining mismatches in transactions-unified are now concentrated in transaction edge/retry behavior (20 mismatches), so adapter wiring is in place but parity is not complete yet.

[midagedev]

Completed on main with current R3 evidence.

What changed:

• Added UTF transaction lifecycle adapter coverage and real-mongod execution parity for transaction paths.
• Added terminal transaction state handling (commit retry semantics, abort after commit, write-conflict commit handling).
• Added transaction-focused regression tests for commit/abort replay and conflict behavior.

Verification:

• ./.tooling/gradle-8.10.2/bin/gradle --no-daemon test
• ./.tooling/gradle-8.10.2/bin/gradle --no-daemon r3FailureLedger -Pr3SpecRepoRoot=/tmp/mongodb-specifications-1771915416 -Pr3FailureLedgerMongoUri='mongodb://127.0.0.1:27017/?replicaSet=rs0&retryWrites=false&directConnection=true' -Pr3FailureLedgerOutputDir=build/reports/r3-failure-ledger-local
• Result: failureCount=0; transactions-unified mismatch/error 0/0.