winch: Improve tunables/configuration validation

[saulecabrera]

This commit introduces proper validation and documentation to handle the engine features not currently supported by Winch (e.g., consume_fuel, follow-up to the discussion in
#9472).

In this commit, the tunables validation is done at the set_tunables method in Winch's wasmtime_environ::compile::CompilerBuilder implemetation, which enables removing Winch specific logic from Config::validate

This change also introduces the question of how to consolidate the compiler specific flags with Winch (e.g, the user-specified cranelift_* options) given that not all of them are applicable to Winch (e.g., cranelift_debug_verifier,
cranelift_nan_canonicalization), this change doesn't introduce any functionality on this front, however, it's probably something worth considering/discussing.

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Label Messager: wasmtime:config

It looks like you are changing Wasmtime's configuration options. Make sure to
complete this check list:

• If you added a new Config method, you wrote extensive documentation for
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  Short, simple summary sentence.
  
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  information about not just the method, but its parameters and results as
  well.
  
  Is this method fallible? If so, when can it return an error?
  
  Can this method panic? If so, when does it panic?
  
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  Optional example here.
  

• If you added a new Config method, or modified an existing one, you
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[alexcrichton]

For the fuzz failure I might recommend updating somewhere around here to switch back to Cranelift if epochs (or other Winch-unsupported configs) are enabled during fuzzing

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