fix(chat) Fix chat options are not working (tab spacing/spacing to panel/align tabs to full panel)

[toanqc]

What does this PR do?

The chat options aren't working at all. This PR fixes:

• Tab Spacing options to work correctly. Fixed by fix(chat): restore tab spacing and even out the first scrolling gap #2011
• Fix Spacing to Panel to work
• Fix Align Tabs to Full Panel

The PR also works if the sidebar icon is set to the right side

How was it tested?

Tested directly in-game

Screenshots

Before
"Bottom Spacing to Panel" does nothing
"Align Tabs to Full Panel" does nothing

After

Checklist

• New settings default OFF (no behavior change without opt-in)
• Zero cost while disabled: no events registered, no polling, no hooks doing work, no frames built
• Cheap while enabled: event-driven (no polling, no timer-based logic, no per-frame allocations)
• No writes onto Blizzard-owned frames (weak-table pattern used); HookScript/hooksecurefunc only, never SetScript on Blizzard frames
• Tested in-game on live; no version gates or pre-Midnight APIs added