feat: create custom filler that automatically add gas buffer (#210)

* feat(superalloy): add filler that includes a gas buffer

* feat(onlyswaps-solver): update fillers to add custom gas buffer

* feat(config): add optional tx_gas_buffer parameter to NetworkConfig

* refactor: add recommended_fillers in superalloy

* feat(onlyswaps-verifier): use recommended fillers with gas buffer in onlyswaps-verifier

* fix(superalloy): remove cfg feature = fillers

* feat(superalloy/fillers): allow setting gas price buffer to `GasBufferFiller`

* feat(onlyswaps-*): add support for custom gas price buffer

Author: azixus

bin/onlyswaps-solver/Cargo.toml

@@ -23,4 +23,4 @@ shellexpand = "3.1.1"
 superalloy.workspace = true
 thiserror.workspace = true
 tokio = { workspace = true, features = ["rt-multi-thread", "signal"] }
-tracing.workspace = true
+tracing.workspace = true