refactor(providers): derive provider options from ConfidenceOptions

[nicklasl]

Summary

• Replace hand-written provider options types with Omit<ConfidenceOptions, 'environment' | 'library' | 'context'> in both web and server provider factories
• Eliminates type drift between ConfidenceOptions and provider options, so passing a ConfidenceOptions object to createConfidenceWebProvider / createConfidenceServerProvider just works
• All new ConfidenceOptions fields (e.g. logger, cache, disableTelemetry) are now automatically available through the provider factories

Test plan

• yarn build passes
• All 159 tests pass
• Verify downstream consumers compile without changes

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