fix: fail if memtrack isn't supported

[not-matthias]

Reworked the shared FIFO handler to first run handle_cmd which allows overriding the commands. Then added a check in SetVersion to check for minimum required version

[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks

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_{Comparing cod-1971-fail-if-memory-isnt-supported-by-integration (d706f21) with main (3150477)}

[Copilot]

Pull request overview

This PR refactors the FIFO command handling to allow executor-specific overrides of commands before falling back to shared implementation. It adds version checking in the memory executor to fail early if the integration doesn't support memory profiling (protocol version < 2).

Changes:

• Refactored handle_fifo_messages to use a two-stage approach: executor-specific handler first, then shared implementation
• Added protocol version check in memory executor to enforce minimum version 2 requirement
• Updated return type from FifoCommand to Option<FifoCommand> for the handler callback

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/executor/shared/fifo.rs	Refactored command handling to invoke custom handler first, then fall back to shared implementation; added default error response for unhandled commands
src/executor/wall_time/perf/mod.rs	Updated perf executor to return Option<FifoCommand> and removed duplicate error handling
src/executor/memory/executor.rs	Added SetVersion command handler to check for minimum protocol version 2

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[GuillaumeLagrange]

tests are failing, not sure why, ping me for quick re-review

[GuillaumeLagrange]

lgtm