[executor] End-to-end pipeline wiring: scanner → profit calc → router → tx builder

[obchain]

Context

The first time everything hangs together. listen subcommand of the CLI should:

1. Spawn the block listener
2. Feed blocks into the health scanner
3. Promote liquidatable positions through the profit calculator
4. Route through the flash-loan router
5. Hand off to the tx builder + simulator

This is the moment we can see "would liquidate X for $Y profit" appear in the logs end-to-end, even without a deployed contract or signer.

Scope

• Wire all crates together in charon-cli/src/main.rs under the listen subcommand
• ProfitCalculator: gross = collateral × bonus_bps / 10000, net = gross - gas - flash_fee - slippage_estimate
• Drop opportunities below bot.min_profit_usd from config
• Each stage logs what it consumed and what it emitted
• No signing / no broadcast — pipeline ends at the simulation gate

Acceptance criteria

• cargo run -- --config config/default.toml listen runs the full pipeline
• For each block: scanner → profit calc → router → tx builder logs are visible in order
• Unprofitable opportunities are dropped with a DEBUG log
• Profitable opportunities log the full encoded tx (hex) and the simulation result
• Runs 5+ minutes against BSC mainnet without panicking

References

• PRD section 2b (Hot-Path Sequence)
• PRD Diagram 02 (End-to-End Hot Path)

[obchain]

Superseded — end-to-end pipeline shipped in feat/17-cli-e2e-pipeline.