fix gpt 5.4 tool calling with reasoning

[j4ys0n]

No description provided.

[Copilot]

Pull request overview

Updates the OpenAI Chat Completions parameter mapping for GPT‑5 family models to handle a model-specific incompatibility between reasoning_effort and function tools (notably gpt-5.4).

Changes:

• Add a GPT‑5 support capability flag to indicate whether function tools can be used alongside reasoning_effort.
• Update OpenAIMapper to omit reasoning_effort when the selected GPT‑5 model does not support it with function tools.
• Add a unit test covering the gpt-5.4 + function tools behavior, and bump package version.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
tests/unit/core/mapping/openai.mapper.spec.ts	Adds coverage to ensure reasoning_effort is omitted for gpt-5.4 when function tools are present.
src/core/mapping/openai.mapper.ts	Implements conditional omission of reasoning_effort based on model support + presence of tools.
src/core/mapping/gpt5.support.ts	Extends GPT‑5 support metadata with supportsFunctionToolsWithReasoning and sets gpt-5.4 to false.
package.json	Bumps SDK version from 1.12.0 to 1.12.1.

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