fix(clob): invalidate version and V2 fee caches

[birchrust]

Fixes invalidate_internal_caches() so it also clears V2 fee metadata, token-to-condition mapping, and cached protocol version.

This prevents order creation from reusing stale V2 fee parameters or an outdated CLOB version after explicit cache invalidation.

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Note

Medium Risk
Medium risk because it changes cache invalidation semantics for fee/version resolution, which can alter when extra HTTP calls occur and what fee parameters are used for order sizing.

Overview
Ensures Client::invalidate_internal_caches() fully resets all CLOB market configuration state by additionally clearing V2 fee metadata (fee_infos), token→condition mappings, and the cached /version result (reset to 0).

Adds a regression test asserting that after invalidation the client re-fetches version and re-primes market info via /markets-by-token + /clob-markets, preventing reuse of stale V2 fee parameters.

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