feat: prepare for calling osaka tracer

[letypequividelespoubelles]

This PR implements issue(s) #

Checklist

• I wrote new tests for my new core changes.
• I have successfully ran tests, style checker and build against my new changes locally.
• I have informed the team of any breaking changes if there are any.

---

Note

Replace switch-case hardfork-to-tracer mapping with fromMainnetHardforkIdToTracerFork across sequencer components.

• Tracing/Sequencer:
  • Replace manual switch mapping of HardforkId.MainnetHardforkId to tracer Fork with fromMainnetHardforkIdToTracerFork(...) in:
    • rpc/methods/LineaEstimateGas#createLineCountingTracer
    • txpoolvalidation/validators/SimulationValidator#createLineCountingTracer
    • txselection/selectors/TraceLineLimitTransactionSelector.LineCountingTracerWithLog constructor
  • Explicitly cast getNextBlockHardforkId(...) to HardforkId.MainnetHardforkId and simplify tracer instantiation (ZkTracer/ZkCounter).

^{Written by Cursor Bugbot for commit 50fed93. This will update automatically on new commits. Configure here.}

[cursor]

Bug: Unsafe Hardfork Cast Breaks Future Compatibility

The unsafe cast from HardforkId to HardforkId.MainnetHardforkId will throw a ClassCastException if getNextBlockHardforkId returns a non-mainnet hardfork ID, such as testnet forks or new fork types. The previous switch statement with a default case provided clearer error handling for unknown fork IDs.

 

[fab-10]

This is fine, but at some time I would like to use HardforkId.MainnetHardforkId everywhere, also in the Tracer, to avoid having to do the conversion