fix: treat new expression references in template as possibly dynamic

[trueadm]

Fixes #10629.

This is an interesting one, but one I think worth considering. When a binding is passed into a template such as

<div>{foo}</div>

When we check if foo is dynamic, unless it comes from state or a prop, it will generally be considered as not dynamic as its just an identifier (member expressions and call expressions are always treated as dynamic). Maybe we can tweak this so that if we see it comes from a new expression that is gets treated as being possibly dynamic. That's because classes are more likely to have a custom toString that might be reactive, thus the identifier itself might be dynamic.

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[dummdidumm]

See #10629 (comment) and #10629 (comment) - we can't possibly statically analyze all cases, so there will still be false positives. I'm not sure yet if that puts me into the camp of "rather be consistent and make the gotcha obvious earler" or "try to make the gotcha appear less often" as this PR would.

[Evertt]

@trueadm @dummdidumm why not do the opposite behavior?

Why not assume that anything could be dynamic and should therefor better be rendered in the template using render_effect()?

As far as I can see, in the worst case scenario you put something in render_effect() that isn't dynamic and you lose a negligible amount of performance. Only the very first render will have a tiny bit of overhead, but after that no re-renders will happen anyway.

But on the other hand, currently there are many scenarios where a variable that was meant to be dynamic is not recognized as such, and so is rendered outside of a render_effect() and therefor is not rendered reactively. This would solve that.