feat: api: add an FEVM events threshold start epoch configuration option

[i-norden]

Related Issues

This is a QoL addition for FEVM RPC providers. As a node operator serving FEVM data it is useful to be able to define a static starting epoch at which we begin supporting returning filtered log events, e.g. at the epoch where a specific contract was deployed. This is in contrast to the existing MaxFilterHeightRange configuration parameter which defines a static range size such that as the chain progresses the supported starting epoch of this window shifts forward.

Proposed Changes

Add and wire in two new configuration parameters:

1. FilterThresholdEpoch a uint64 which defines a specific epoch at and above which the node will support returning log events.
2. FilterThresholdSet a bool which specifies that the node should use FilterThresholdEpoch to define the supported log events range instead of using the moving window defined by MaxFilterHeightRange.

MaxFilterHeightRange is left as the default configuration.

Additional Info

Checklist

Before you mark the PR ready for review, please make sure that:

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