fix(macro)!: argument metadata from the type, not from its spelling

[ptondereau]

Description

Argument nullability, pass-by-reference and variadics now come from constants on FromZval/FromZvalMut instead of matching type names, so aliases and qualified paths get the right PHP signature.

Object arguments are passed by value, optional nullable arguments declare a null default, and Default/Clone are detected through the type system.

Checklist

• I have read the contribution guidelines and the code of conduct.
• I have added tests that prove my code works as expected.
• I have added documentation if applicable.
• I have added a migration guide if applicable.

[codspeed]

Merging this PR will not alter performance

✅ 30 untouched benchmarks

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_{Comparing fix/dx1-arg-metadata-from-traits (51d2af0) with master (a8d5d9c)}

[coveralls]

Coverage Report for CI Build 35765197921

Coverage increased (+0.08%) to 69.628%

Details

• Coverage increased (+0.08%) from the base build.
• Patch coverage: 38 uncovered changes across 4 files (259 of 297 lines covered, 87.21%).
• No coverage regressions found.

Uncovered Changes

File	Changed	Covered	%
src/internal/class.rs	18	0	0.0%
src/convert.rs	78	68	87.18%
src/types/array/mod.rs	6	0	0.0%
src/args.rs	68	64	94.12%
Total (7 files)	297	259	87.21%

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	13891
Covered Lines:	9672
Line Coverage:	69.63%
Coverage Strength:	54.77 hits per line

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💛 - Coveralls