fix keyframes order

[jantimon]

This pull request addresses issue #166, where keyframe animations defined after their usage in styled components cause an "Unsupported template literal in css expression" error. The solution involves the following key changes:

• Introduced ScopedVariableReference to manage JavaScript variable references more effectively, ensuring that both simple and complex references (e.g., foo and foo.bar) are handled consistently
• Updated the handling of keyframe animations and nested CSS expressions to resolve references correctly, even when keyframes are defined after their usage

The solution is to link keyframe references with its declaration even before it was declared and reuse this name later during the actual declaration. This ensures that animations work seamlessly regardless of their order in the file

[jantimon]

This PR added support for keyframes in objects e.g.:

• const foo = { bar: keyframes`...` }

The first version supported only identifiers so the following versions were ignored:

• const foo = { "bar": keyframes`...` }
• const foo = { 123: keyframes`...` }

So in this update I enhanced visit_mut_object_lit function to support more types of the PropName:

• Ident: Uses the sym field directly
• Str: Uses the value field
• Num: Converts to string
• BigInt: Converts to string
• Computed: Skipped (cannot be statically analyzed)

I also added an additional test

[Tyderion]

lgtm