fix(layout_strategies): odd flex layout default behavior

[ronandalton]

Description

This PR fixes an issue with the flex layout by changing the default values for flip_columns and flip_lines to match the preview_cutoff values for the horizontal and vertical layouts. This should improve the user experience for users who have their default layout set to 'flex'. See the issue description linked below for more information.

Fixes #3138

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

The change implemented in this PR was tested using the following two tests:

• Test A: Set default layout_strategy to 'flex' with no additional configuration. Run :Telescope live_grep and resize window. Observe that layout changes to vertical when width < 120 given height >= 40.
• Test B: Set default layout_strategy to 'flex' and layout_config.horizontal.preview_cutoff and layout_config.vertical.preview_cutoff to custom values. Run :Telescope live_grep and resize window. Observe that layout changes to vertical when the window size matches the preview_cutoff values set.

Configuration:

• Neovim version (nvim --version): NVIM v0.10.0
• Operating system and version: Linux 6.8.1

Checklist:

• My code follows the style guidelines of this project (stylua)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (lua annotations)

[Conni2461]

yep that is actually a problem, good catch and thanks for the fix :)