fix(semantic): match a pattern subtree only against a call subtree with the same delimiters

[orizi]

The MacroElement::Subtree matching arm never compared the delimiter kind of the pattern subtree
against the input subtree, so a rule ([$x:ident]) matched the call m!({a}). Compare the
delimiter kinds, treating a mismatch as a rule-match failure so a later rule may still match, as
rustc does.

Also resolves the adjacent TODO(Dean) about bracket terminal consistency: a pattern subtree
cannot have inconsistent delimiters in the AST, and a pattern missing a closing delimiter is
reported by the parser and its rule is already dropped - so no declaration time check is needed.

[reviewable-StarkWare]

This change is 

[orizi]

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• test(semantic): pin the rejection of an expansion zipping sibling repetitions #10316
• fix(semantic): reject a + expansion repetition over zero groups #10315
• doc(semantic): document the macro expansion error arms as defensive #10314
• fix(semantic): reject a trailing macro repetition separator like rustc #10313
• feat(semantic): match and emit non-comma macro repetition separators #10312
• feat(parser): accept any single-token macro repetition separator #10311
• refactor(syntax): generalize the macro repetition separator node #10310
• fix(semantic): parenthesize an expression capture spliced into an expansion #10309
• fix(semantic): keep the trailing trivia of an expansion's placeholders and blocks #10308
• fix(semantic): capture an expr placeholder by what the parser consumed #10307
• test(semantic): pin the macro matcher behaviors that already agree with rustc #10306
• fix(semantic): reject a pattern that follows an expr placeholder with a token it would swallow #10305
• fix(semantic): reject the malformed macro rule declarations that silently do nothing #10304
• fix(semantic): match a pattern subtree only against a call subtree with the same delimiters #10303 👈 (View in Graphite)
• fix(semantic): reject a macro rule pattern that reuses a placeholder name #10302
• fix(semantic): expand a macro repetition over its own group of captures #10301
• test(semantic): pin the macro repetition operator and trailing separator behaviors #10300
• refactor(semantic): build a nested capture tree alongside the flat macro captures #10299
• fix(semantic): reject a macro expansion block with nothing repeating at its depth #10298
• fix(semantic): report macro expansion failures instead of panicking #10297
• main

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[cursor]

PR Summary

Medium Risk
Changes core user-defined macro matching in the semantic layer; behavior shifts for calls that previously matched across delimiter kinds, but scope is localized and heavily tested.

Overview
User-defined inline macro rule matching now treats subtree delimiter kind ((), [], {}) as part of the pattern, aligned with rustc: a rule like ([$x:ident]) no longer matches macro!({a}).

In macro_declaration.rs, the MacroElement::Subtree arm pairs WrappedMacro / WrappedTokenTree variants before recursing; a mismatch fails the rule (not a user error) so later rules can still match. The TODO on verifying bracket terminals at declaration time is removed—the parser already rejects inconsistent delimiters and drops broken rules.

Tests cover multi-rule fallback, nested inner subtrees, non-first subtree elements, empty {} vs [], and E2158 when no rule fits.

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