refactor(chip): improve selection model and MD3 compliance

[ruben-rebelo]

Refactor Chip to improve Material Design 3 compliance, remove problematic children patterns, improve performance characteristics, and modernize the public API.

Problems

• Current API relies heavily on children composition in ways that are difficult to optimize
• Internal layout logic is tightly coupled to arbitrary child structures
• MD3 behaviors and visuals are not fully aligned with current Material guidelines
• Rendering performance can degrade in large lists or frequently updated screens
• Type safety and discoverability of the API can be improved
• The component has inconsistent behavior between platforms and edge cases

Focus Areas

• Improve selected/outlined/filter states
• Improve icon/avatar handling
• Simplify content rendering
• Improve touch target sizing
• Improve state layer implementation

Proposed API Direction

Move toward explicit label APIs:

<Chip label="Filter" selected />

Performance Opportunities

• Reduce animation overhead
• Avoid child inspection
• Improve memoization
• Simplify icon rendering path