Workload Rewrite: Monolithic Fuzzer → Weighted Stress Engine

[parthshah1]

Replaced the shell-script-driven CLI workload with a single-binary weighted stress engine. Branch: [parth/workload-upgrade](https://github.com/FilecoinFoundationWeb/Filecoin-Antithesis/pull/163).

What Changed (done)

Architecture

• Split monolithic main.go + resources/*.go (14 files, 3573 lines) into genesis-prep + stress-engine binaries
• Deleted 8 shell driver scripts (parallel_driver_spammer.sh, anytime_state_checks.sh, etc.)
• Weighted action deck with STRESS_WEIGHT_* env vars — weights of 0 disable a vector
• Antithesis deterministic randomness (random.GetRandom(), random.RandomChoice())

Stress Vectors — 14 implemented (was ~5)

• DoTransferMarket — random FIL transfers
• DoGasWar — concurrent txns competing for gas
• DoHeavyCompute — heavy actor method calls
• DoAdversarial — malformed messages (bad nonce, zero gas, oversized params, invalid signature)
• DoChainMonitor — cross-node consensus, state roots, tipsets, height spread, peer count, deep audit
• DoDeployContracts — EVM contract deployment with deferred verification
• DoContractCall — delegatecall, SimpleCoin transfer, external recursion
• DoSelfDestructCycle — deploy → interact → destroy → verify across nodes
• DoConflictingContractCalls — concurrent conflicting calls from different nodes
• DoGasGuzzler / DoLogBlaster / DoMemoryBomb / DoStorageSpam
• DoReorgChaos — reorg-inducing patterns (weight=0 default)

Assertions — 42 properties (was ~10)

16 Always + 26 Sometimes across consensus, EVM, mempool, and reorg domains.

Build

• Dockerfile: 106 → 30 lines. Removed Node.js, Rust, Foundry, Hardhat, synapse-sdk
• Entrypoint: 502 → 44 lines. Only: genesis wallets → wait env → setup_complete → stress engine

Remaining

• Merge [parth/workload-upgrade](https://github.com/FilecoinFoundationWeb/Filecoin-Antithesis/pull/163) to main — PR review needed
• Regression gate — push updated images, 1-hour Antithesis run, verify all 42 assertions pass
• Add WindowPoSt timing stress (messages at proof deadline boundaries)
• Add message pool consistency (compare pending messages across nodes)
• Add chain finality property (Always: finalized tipsets never revert)
• Add versioned config for network upgrade testing.

Closes #152, #153, #162