[DOC] update kwargs/methods in docs

[36000]

No description provided.

[Copilot]

Pull request overview

This PR updates the documentation for kwargs and methods reference files to reflect recent changes in the codebase, including new parameters, reorganized sections, and updated descriptions.

Changes:

• Added new STRUCTURAL section in kwargs.rst with brain_mask_definition parameter
• Added new TISSUE section in kwargs.rst with PVE and MSMT-related parameters
• Reorganized and updated method descriptions in methods.rst, including new entries for tissue segmentation models (synthseg_model, mx_model) and moved T1w-related parameters
• Updated default values and descriptions for various parameters including ray_n_cpus, numba_n_threads, reg_subject_spec, and scalars

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 10 comments.

File	Description
docs/source/reference/methods.rst	Reorganized parameter ordering, added new tissue segmentation and T1w parameters, removed deprecated MSMT and endpoint parameters from old locations and moved them to more logical positions
docs/source/reference/kwargs.rst	Added STRUCTURAL and TISSUE sections, updated parameter descriptions to reflect current implementation, reorganized MSMT parameters into TISSUE section

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[Copilot]

Missing space after "This is" - should be "This is useful if generating GIFs in a headless environment." The word "useful" appears to be missing from the description.

Suggested change

	Whether to use a virtual frame buffer. This is if generating GIFs in a headless environment. Default: False
	Whether to use a virtual frame buffer. This is useful if generating GIFs in a headless environment. Default: False