refactor(parser): Modifiers::add take Modifier as param

[overlookmotel]

Refactor. Simplify signature of Modifiers::add by making it take just Modifier instead of a ModifierKind + u32 pair. Modifier contains the same data.

[overlookmotel]

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• refactor(parser): Modifiers::add take Modifier as param #20825 👈 (View in Graphite)
• refactor(parser): make Modifier Copy #20824
• perf(parser): defer calculation of Modifier spans #20823 : 1 other dependent PR (#20826 )
• perf(parser): remove branch from parse_modifiers #20821
• perf(parser): reduce Kind to ModifierKind conversions in eat_modifiers_before_declaration #20820
• refactor(parser): shorten code handling illegal modifiers #20781
• perf(parser): fast path for no syntax errors when checking modifiers #20748
• perf(parser): remove a lookahead from eat_modifiers_before_declaration #20755
• refactor(parser): nest modifiers types in modules #20754
• refactor(parser): re-order modifiers code #20753
• perf(parser): store Modifiers on stack #20742
• perf(parser): add Modifiers::get method #20741
• refactor(parser): rename ModifierKinds::empty to none #20740
• refactor(parser): rename ModifierFlags to ModifierKinds #20739
• refactor(parser): simplify ModifierFlags #20738
• refactor(parser): import from std at top level #20737
• refactor(parser): remove Modifier::is_static() #20736
• refactor(parser): remove dead code from modifier parsing #20735
• main

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[Copilot]

Pull request overview

Refactors the parser’s modifier bookkeeping to pass Modifier values directly, reducing parameter duplication and aligning call sites around a single value type that already encapsulates span_start + kind.

Changes:

• Make Modifier::new a const fn to allow construction in const contexts.
• Change internal Modifiers::add to accept a Modifier instead of (ModifierKind, u32).
• Update modifier parsing call sites to use the new add(Modifier) signature.

[codspeed-hq]

Merging this PR will not alter performance

✅ 48 untouched benchmarks
⏩ 8 skipped benchmarks¹

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_{Comparing om/03-28-refactor_parser_modifiers_add_take_modifier_as_param (881a81f) with om/03-28-refactor_parser_make_modifier_copy_ (bbef4f3)}

Footnotes

1. 8 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[overlookmotel]

This depended on #20824, which I've closed because it was a small perf regression. So closing this too.