feat(builder): support multiple flashbots builders

[dancoombs]

Closes #283

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 1.31579% with 150 lines in your changes are missing coverage. Please review.

Project coverage is 54.97%. Comparing base (c0d5235) to head (cf5c881).

:exclamation: Current head cf5c881 differs from pull request most recent head d236c3e. Consider uploading reports for the commit d236c3e to get more accurate results

Additional details and impacted files

[](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | [Files](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | Coverage Δ | | |---|---|---| | [crates/builder/src/sender/bloxroute.rs](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&filepath=crates%2Fbuilder%2Fsrc%2Fsender%2Fbloxroute.rs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#diff-Y3JhdGVzL2J1aWxkZXIvc3JjL3NlbmRlci9ibG94cm91dGUucnM=) | `0.00% <ø> (ø)` | | | [crates/types/src/chain.rs](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&filepath=crates%2Ftypes%2Fsrc%2Fchain.rs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#diff-Y3JhdGVzL3R5cGVzL3NyYy9jaGFpbi5ycw==) | `88.88% <100.00%> (+0.88%)` | :arrow_up: | | [crates/builder/src/task.rs](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&filepath=crates%2Fbuilder%2Fsrc%2Ftask.rs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#diff-Y3JhdGVzL2J1aWxkZXIvc3JjL3Rhc2sucnM=) | `0.00% <0.00%> (ø)` | | | [crates/builder/src/sender/mod.rs](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&filepath=crates%2Fbuilder%2Fsrc%2Fsender%2Fmod.rs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#diff-Y3JhdGVzL2J1aWxkZXIvc3JjL3NlbmRlci9tb2QucnM=) | `1.25% <0.00%> (+0.22%)` | :arrow_up: | | [bin/rundler/src/cli/builder.rs](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&filepath=bin%2Frundler%2Fsrc%2Fcli%2Fbuilder.rs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#diff-YmluL3J1bmRsZXIvc3JjL2NsaS9idWlsZGVyLnJz) | `0.00% <0.00%> (ø)` | | | [crates/builder/src/sender/flashbots.rs](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701?src=pr&el=tree&filepath=crates%2Fbuilder%2Fsrc%2Fsender%2Fflashbots.rs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#diff-Y3JhdGVzL2J1aWxkZXIvc3JjL3NlbmRlci9mbGFzaGJvdHMucnM=) | `0.00% <0.00%> (ø)` | | | [Flag](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | Coverage Δ | | |---|---|---| | [unit-tests](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `54.97% <1.31%> (-0.19%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform#carryforward-flags-in-the-pull-request-comment) to find out more. | [Components](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=components&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | Coverage Δ | | |---|---|---| | [rundler binary](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `0.00% <0.00%> (ø)` | | | [builder](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `50.02% <0.00%> (-0.58%)` | :arrow_down: | | [dev](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `0.00% <ø> (ø)` | | | [pool](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `64.87% <ø> (ø)` | | | [provider](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `14.77% <ø> (ø)` | | | [rpc](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `25.46% <ø> (ø)` | | | [sim](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `77.51% <ø> (ø)` | | | [tasks](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `∅ <ø> (∅)` | | | [types](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `65.92% <100.00%> (+0.04%)` | :arrow_up: | | [utils](https://app.codecov.io/gh/alchemyplatform/rundler/pull/701/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=alchemyplatform) | `18.28% <ø> (ø)` | |