fix: enable horizontal scrolling for long lines in SQL editor

[datlechin]

Summary

• Fix horizontal scrolling for long lines when word wrap is off
• Vendor CodeEditTextView as local package to fix upstream bug
• Remove fragile workaround from SQLEditorCoordinator

Root Cause

Variable shadowing bug in CodeEditTextView's TextLayoutManager+Layout.swift:190:

var maxFoundLineWidth = maxFoundLineWidth // shadows inout param with local copy

This created a local variable that shadowed the inout parameter. Line widths were measured but written to the local copy, discarded on return. maxLineWidth stayed at 0, estimatedWidth() always returned ~56px (just edge insets), and the text view frame never expanded beyond the clip view width.

Changes

• CodeEditTextView (vendored as local package): removed the shadowing var declaration — one line fix
• CodeEditSourceEditor (styleTextView): conditionally set TAMIC based on wrapLines; added hasHorizontalScroller to styleScrollView
• SQLEditorCoordinator: removed entire horizontal scroll workaround (3 methods, observer, delayed check) — replaced with clean installEditorSettingsObserver for vim settings only

Test plan

• Type a long line (>150 chars) with word wrap off — editor scrolls horizontally
• Toggle word wrap on/off in settings — horizontal scroll toggles correctly
• Switch dark/light mode — horizontal scroll still works
• Change font size — horizontal scroll still works