Replace javascript-natural-sort package with inline ESM implementation

[andreialecu]

Summary

• Replaces the CommonJS-only javascript-natural-sort dependency with an inline ESM module
• Eliminates the "Module 'javascript-natural-sort' is not ESM" warning in Angular and other ESM-first bundlers
• Enables proper tree-shaking of this code

Part of #3649

Details

The javascript-natural-sort package hasn't been updated in 9+ years and only ships CommonJS. Rather than waiting for an upstream ESM build, this inlines the implementation as a clean ESM module.

The implementation preserves the original algorithm while improving readability (descriptive variable names, extracted helper functions) and performance:

Dataset	Original	Inline	Speedup
strings (1000)	13.7ms	11.0ms	+19%
numbers (1000)	7.2ms	5.3ms	+26%
mixed (1000)	9.1ms	7.3ms	+20%
versions (1000)	12.6ms	10.1ms	+20%

Key optimizations: charCodeAt instead of regex for leading-zero detection, .test() instead of .match() to avoid array allocations, hoisted inline regex literals to module-level constants, removed per-call closure allocation.

Output is verified identical to the original package across all test data.

Test plan

• New unit tests for the naturalSort module (34 tests: all upstream cases + edge cases for null, boolean, Infinity, scientific notation, large numbers, global regex stability)
• Existing compareNatural.test.js tests pass (20 tests)
• All 6670 unit tests pass
• Lint passes with zero warnings