feat: implement Claude 4.x model handling in invocation parameters

[jash0803]

• Added support for Claude 4.x models to ensure only one of temperature or top_p can be set.
• Introduced isClaude4 utility function to check model type.
• Updated InvocationParametersFormFields to handle disabling fields based on model type.
• Modified applyAnthropicInvocationParameterConstraints to filter parameters accordingly.
• Adjusted playground_clients.py to remove top_p if temperature is set for Claude 4.x models.

Fixes #11278

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Note

Medium Risk
Touches both UI state management and server request parameter shaping for Anthropic models; mistakes could silently alter sampling behavior (e.g., unexpectedly dropping top_p) for Claude 4.x invocations.

Overview
Adds Claude 4.x model detection and enforces the provider constraint that only one of temperature or top_p may be set.

In the playground UI, setting one parameter now clears the other and the conflicting field is disabled to provide visual feedback. On the request path, Anthropic invocation-parameter constraints and the server-side AnthropicStreamingClient both drop top_p when both are present (preferring temperature) to avoid invalid Claude 4.x calls.

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[cursor]

Both fields disabled when temperature and top_p both set

Medium Severity

The isDisabled logic disables temperature when top_p is set and disables top_p when temperature is set. If both values are present simultaneously (e.g., after switching from a non-Claude-4 model where both were configured), both fields become disabled and the user is stuck — neither slider can be interacted with. Since the onChange handler that enforces mutual exclusion only runs on user interaction, there's no way to recover from this state. The condition needs to account for the "both set" case, for example by only disabling top_p when temperature is set (matching the "prefer temperature" behavior used elsewhere).

 

[jash0803]

this flag is for claude 4 models

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Top_p slider permanently disabled on Claude 4 models

Medium Severity

The isDisabled check for top_p evaluates values["temperature"] != null, but temperature always has a default value of 1.0 (via mergeInvocationParametersWithDefaults). Since there's no UI mechanism to "clear" a slider value back to undefined/null, this makes top_p permanently disabled on all Claude 4 models. The mutual exclusion effectively becomes one-directional — temperature always wins — and users can never opt to use top_p instead.

Similarly, if both values are already present when switching from a non-Claude-4 model (e.g., user set top_p on Claude 3 then switches to Claude 4), both sliders become disabled simultaneously, creating a UI deadlock with no way to resolve the conflict.