Fixed Docked resizing + added docking restrictor

[yagarifullin]

Fix docked window resize behavior and add per-window dock restrictions

• Prevent docked windows from undocking during resize by always
  calling AlterOptions for tethered windows and resetting position
  deltas when resize ends
• Fix Right dock X position recalculation after resize (X = ViewW - W)
• Fix Bottom dock Y position recalculation after resize (Y = ViewH - H)
• Add DisableDocks option to restrict specific dock types per window
  (e.g., DisableDocks = {'Bottom'} prevents docking to bottom edge)

[flamendless]

Thank you for the PR!

[flamendless]

Add DisableDocks option to restrict specific dock types per window
(e.g., DisableDocks = {'Bottom'} prevents docking to bottom edge)

@yagarifullin you also need to add that new option in the documentation in API.lua.
Also here https://github.com/flamendless/Slab/wiki (hopefully you have access to edit it)

[yagarifullin]

Sorry, I don't have access to edit the wiki.

The idea for this feature came up when I realized that controls laid out vertically don't automatically rearrange into a horizontal layout when docked to Bottom. So I added this option to keep vertically arranged windows vertical everywhere. But it works for other sides as well.

DisableDocks is a list of dock types to disable for a specific window. Valid values are 'Left', 'Right', 'Bottom'. When set, the dock overlay for the specified sides will not appear while dragging that window.

Example: DisableDocks = {'Bottom'}

Slab.BeginWindow("MyWindow", {
Title = "My Window",
W = 300, H = 300,
DisableDocks = {'Bottom'},
})

[flamendless]

Sorry, I don't have access to edit the wiki.

The idea for this feature came up when I realized that controls laid out vertically don't automatically rearrange into a horizontal layout when docked to Bottom. So I added this option to keep vertically arranged windows vertical everywhere. But it works for other sides as well.

DisableDocks is a list of dock types to disable for a specific window. Valid values are 'Left', 'Right', 'Bottom'. When set, the dock overlay for the specified sides will not appear while dragging that window.

Example: DisableDocks = {'Bottom'}

Slab.BeginWindow("MyWindow", {
Title = "My Window",
W = 300, H = 300,
DisableDocks = {'Bottom'},
})

Thank you for the explanations! I'll merge it once the changes in API.lua has been made