[P1] Fix file browser clipping/bleed and tree alignment

[currentsuspect]

Goal

Resolve file browser visual bleed and tree alignment inconsistencies.

Scope

• Fix clipping/bleed at panel boundaries.
• Normalize indentation/alignment for nested tree rows.
• Verify hover/selection backgrounds stay within row bounds.

Acceptance Criteria

• No bleed artifacts when scrolling/resizing.
• Tree indentation is visually consistent at all depths.
• Selection/hover painting respects clipping.

[currentsuspect]

Progress Update

Scope

Fixed file browser visual clipping/bleed and tree alignment issues as specified in acceptance criteria.

Files Modified

• Source/Components/FileBrowser.cpp (13 insertions, 8 deletions)

Changes Implemented

1. Clip Rect Coverage (Bleed fix)

   • Extended clip rect by 1px on all sides to ensure full panel boundary coverage
   • Prevents rendering artifacts at panel edges during scroll/resize

2. Rounded Rect Radius Capping (Bleed fix)

   • Selected state: radius capped to min(6.0f, itemHeight/3)
   • Hover state: radius capped to min(4.0f, itemHeight/4)
   • Prevents visual bleed into adjacent rows when item height is small (22px default)

3. Tree Guide Line Alignment (Alignment fix)

   • Removed rowIndentStep * 0.5f offset from guide line X calculation
   • Guide lines now properly align with expander arrow positions at all depths
   • Consistent indentation visualization for nested tree rows

Validation

• ✅ CMake configure: Success
• ✅ Build: Success (all targets compiled)
• ✅ Stable tests: 5/5 passed (MathTests, FileTests, ThreadingTests, LogTests, ConfigAssertTests)

Commit

a0dc629 - fix(FileBrowser): #122 Fix clipping/bleed and tree alignment

Remaining Work

• Visual QA testing in UI (requires interactive verification)
• Verify fix across different DPI/scaling settings