fix(babel-plugin,compiler): assign bare variable refs inside ref arrays (#3285)

[javascript-unsafe]

Closes #3285

What was broken

<div ref={[el]} /> compiled without errors and passed type-checking, but el was never assigned the element:

let el;
render(() => <div ref={[el]} />, document.body);
el; // undefined ❌

while the callback form worked:

let el;
render(() => <div ref={[(node) => (el = node)]} />, document.body);
el; // <div> ✅

Why

• A plain ref={el} works: the compiler emits a callback that assigns the element to el when it's not callable.
• ref={[el]} took a different branch — the array was passed through untouched (wrapped as _$ref(() => [el], element)), with nothing done to the el inside.
• At runtime, ref arrays are flattened and each entry is called with the element (f && f(element)). A bare variable evaluates to undefined at mount time, so it gets silently skipped and nothing is ever assigned.

The runtime only sees the evaluated value (undefined), not the binding, so this can't be fixed at runtime — the compiler has to turn the bare variable into something callable.

The fix

Both compilers (the babel plugin and the native Rust compiler) now transform ref array literals element by element:

Element in ref array	Behavior
bare let variable ref={[el]}	lowered to an assignment callback, same contract as non-array refs: read the target once; if it currently holds a function, call it with the element; otherwise assign the element
member expression ref={[obj.el]}	same treatment
nested array ref={[[el]]}	recursed
spread ref={[...refs]}	left as-is (already a value)
callback ref={[fn]}, const/module bindings, globals (undefined)	left untouched — assigning to a global like undefined would throw in strict mode
falsy slots null / false	untouched, still short-circuit at runtime

This also preserves the existing let cb = someFn; <div ref={[cb]} /> semantics — someFn gets called with the element rather than cb being overwritten.

Tests

• 9 new behavioral specs in packages/web/test/ref-array.spec.tsx (the issue's case plus multiple variables, callbacks, mixed arrays, member expressions, nested arrays, falsy slots, mutable/const function bindings) — green with both the native compiler and JSX_COMPILER=babel
• new refArrays babel-plugin fixture, reused as an oxc fixture — zero parity diff between the two compilers' output
• full suites green: babel-plugin 257 tests, compiler 5362 JS tests + 55 cargo tests (default / no-default-features / tsrx), clippy -D warnings clean

Changeset

Patch bumps for @solidjs/babel-plugin and @solidjs/compiler.

[changeset-bot]

🦋 Changeset detected

Latest commit: 0479d25

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 11 packages

Name	Type
@solidjs/babel-plugin	Patch
@solidjs/compiler	Patch
test-integration	Patch
@solidjs/diagnostics	Patch
@solidjs/element	Patch
@solidjs/h	Patch
@solidjs/html	Patch
@solidjs/signals	Patch
solid-js	Patch
@solidjs/universal	Patch
@solidjs/web	Patch

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[codspeed-hq]

Merging this PR will not alter performance

✅ 136 untouched benchmarks

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_{Comparing javascript-unsafe:fix/ref-array-lval-3285 (0479d25) with next (ace227e)}