chore(release): 6.0.0

[mastermunj]

🤖 I have created a release beep boop

6.0.0 (2026-08-23)

⚠ BREAKING CHANGES

• Language-only locale tags now resolve to explicit regional defaults, including
  en → en-US, es → es-ES, pt → pt-BR, and sw → sw-KE.
• Initialized locale configurations are recursively frozen. Applications can
  inspect locale configuration, but can no longer mutate it after initialization.
• Public numeric utilities now use stricter, decimal-safe semantics for
  toFixed(), isFloat(), and isNumberZero().
• The CLI now rejects unknown options, repeated locale options, and conflicting
  conversion modes.
• LocaleManifestEntry now requires generated numbering-system and named-range
  metadata.
• Invalid custom locale configurations that violate conversion invariants are
  now rejected.

See the v6 migration guide
for upgrade instructions.

Features

• Add a compact locale capability manifest without loading conversion tables.
• Add public locale-contract validation for custom locale authors.
• Add generated numbering-system, grouping, named-range, and capability metadata.
• Add executable locale conformance and quality gates.
• Generate locale capability and quality documentation from shipped configuration.

Bug Fixes

• Preserve exact large-number input and decimal precision without slowing hot paths.
• Apply decimal-safe currency rounding and preserve negative sub-unit signs.
• Correct Spanish ordinal gender behavior.
• Reset formal locale state between conversions.
• Enforce deterministic locale-table and conversion contracts.

Performance Improvements

• Initialize per-locale functional helper instances lazily.
• Mark package modules as side-effect free for better tree-shaking.
• Reduce the full UMD bundle from 69.72 KiB to 68.46 KiB gzip.
• Add enforced gzip size budgets for the full and per-locale bundles.

Release Quality

• Verify generated documentation, ESM and CommonJS entry points, runtime behavior,
  package contents, and bundle-size budgets before publishing.
• Preserve 100% test coverage across the complete test suite.

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Additional details and impacted files

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  Coverage   100.00%   100.00%            
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  Files          142       142            
  Lines         2158      2158            
  Branches       448       303   -145     
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  Hits          2158      2158            

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[mastermunj]

🤖 Created releases:

• v6.0.0

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