Compilers inline ?? "" for a nullish checkbox/radio value in non-hydratable builds (follow-up to #4009) #4017

Summary

#4009 (closing #4008) fixed the runtime: when a checkbox or radio gets a nullish value, setProperty and the spread path now remove the attribute, so a checked box submits the native "on" instead of "".

Non-hydratable client builds don't reach that path for a direct binding. Both compilers inline the #2957 text-field fallback for value/defaultValue on every input, whatever its type:

• @solidjs/babel-plugin: packages/babel-plugin/src/dom/element.ts L458, t.logicalExpression("??", value, t.stringLiteral("")).
• @solidjs/compiler: the equivalent in packages/compiler/src/dom/set_attr.rs (around L163).

So in a client-only build this still submits "" when v() is nullish:

<input type="checkbox" name="agree" value={v()} checked />

Expected

The build modes should behave the same. When the input's static type is checkbox or radio, or isn't static, a nullish value/defaultValue should remove the attribute, as the runtime does. Text inputs and textarea keep the ?? "" clearing from #2957.

Notes

• Hydratable builds already route these bindings through setProperty, so only the non-hydratable inline path is affected.
• A test should cover both compilers, matching the runtime test from fix(web): preserve default checkbox and radio submission values #4009.

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