feat(transformer): add TraverseCtx::generate_uid

[overlookmotel]

Add TraverseCtx::generate_uid method.

This is modelled on Babel's scope.generateUid() method. As discussed in #3251 (comment), this is required to fix most of the remaining failing tests in transformer Milestone 1.

I have implemented this to work as closely as possible to Babel, so that it will generate same output as Babel for our tests. However, as mentioned in the code comments, this means it's a pretty expensive function to call. Those code comments suggest 2 ways in which we could make it much more efficient, but we'd need to decide how we're going to handle divergence from Babel before we can decide which route to go.

I've left it as a TODO(improve-on-babel) for now.

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[overlookmotel]

• fix(transformer): use UIDs in TS namespace transforms #3395
• feat(transformer): add TraverseCtx::generate_uid #3394 👈
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #3394 will degrade performances by 4.53%

_{Comparing 05-23-feat_transformer_add_traversectx_generate_uid_ (d8489f4) with main (79811ca)}

Summary

⚡ 1 improvements
❌ 2 regressions
✅ 24 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	05-23-feat_transformer_add_traversectx_generate_uid_	Change
⚡	semantic[antd.js]	218.5 ms	210.2 ms	+3.95%
❌	semantic[cal.com.tsx]	55.9 ms	57.9 ms	-3.37%
❌	semantic[pdf.mjs]	34.1 ms	35.7 ms	-4.53%

[overlookmotel]

The semantic benchmarks results are completely spurious. This PR does touch semantic, but only to remove some dead code.

[Dunqing]

Yes, the Babel implementation has a lot of room for improvement. I think once most of the plugins are done, we can move in the direction we think is efficient

[Boshen]

Add comment: this goes through the whole symbol table