docs: Update ui_mode doc [skip tests]

[hpohekar]

closes #3886

Context

Prior to this change, the ui_mode parameter in several parts of the PyFluent codebase had an incomplete or slightly misleading docstring. Users could pass either members of the UIMode enum or specific string literals (e.g. "no_gui", "hidden_gui", etc.), but that flexibility was not well documented. This ambiguity could lead to confusion about which string names are valid and how they map to enum values.

Change Summary

Updated the docstrings in launcher.py, slurm_launcher.py, and session_utilities.py to better describe accepted ui_mode values (both enum and string forms).

Clarified which string names correspond to which UIMode values (e.g. "no_gui_or_graphics", "no_gui", "hidden_gui", "gui", etc.).

Removed or refined outdated or redundant lines in the existing doc comments.

Ensured consistency across the codebase about how ui_mode is explained.

Marked the PR to skip tests, since only docstrings were changed.

Rationale

Better user experience / usability: Clear documentation helps users (and maintainers) know exactly what ui_mode values are supported.

Reduce confusion / errors: Users may try unsupported strings or misuse the enum; this aims to guide them.

Maintain consistency: Before, docstrings in different modules had slight variations or omissions. This change harmonizes those descriptions.

Low risk: Since only documentation is modified (no logic changes), this is a safe improvement.

Impact

Documentation / developer experience: Anyone reading or using code involving ui_mode will get more precise information on acceptable values.

Minimal to no runtime impact: Because no functional logic was changed, existing behavior remains unchanged.

Future maintenance: When extending or deprecating a ui_mode, future contributors can rely on the docstrings being consistent across modules.

Testing: No tests should break (and the PR is marked [skip tests]), but doc validation tools (if present) may pick up formatting or lint changes.

[Copilot]

Pull Request Overview

Updates the docstring for the ui_mode parameter across multiple Fluent launcher files to use consistent terminology and remove the optional designation in one location.

• Standardizes the ui_mode parameter description to use "Defines the user interface mode for Fluent. Options correspond to values in the UIMode enum."
• Removes the detailed explanation of specific UI mode values and version requirements from the main launcher
• Corrects the parameter type from optional to required in session_utilities.py

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/ansys/fluent/core/session_utilities.py	Removes "optional" designation from ui_mode parameter type
src/ansys/fluent/core/launcher/slurm_launcher.py	Updates ui_mode description to use standardized language
src/ansys/fluent/core/launcher/launcher.py	Simplifies ui_mode documentation by removing detailed options and version info

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Pull Request Overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

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