refactor: remove unused SWC helpers

[CPunisher]

Summary

This PR removes the HELPERS (SWC transform helpers) from the Ast context and the minification logic in rspack_javascript_compiler.

This simplifies the AST handling and removes unnecessary overhead from SWC helpers that were not being utilized.

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

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🔨 Latest commit	21a4788
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[Copilot]

Pull request overview

This PR removes unused SWC helper infrastructure from the Ast context and minification logic, simplifying code paths that don't require helper injection capabilities.

• Removes HelperData from the Context struct in the AST module
• Eliminates HELPERS.set wrappers from AST transform/view methods and the minification process
• Cleans up related imports in both affected files

The JavaScriptTransformer in transform.rs correctly retains HELPERS support, as it processes external SWC plugins that may inject helpers.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
crates/rspack_javascript_compiler/src/compiler/minify.rs	Removes HELPERS.set wrapper from minification logic and cleans up the helpers import
crates/rspack_javascript_compiler/src/ast.rs	Removes HelperData field from Context struct, eliminates HELPERS.set calls in transform/view methods, and updates Debug implementation

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[github-actions]

Rsdoctor Bundle Diff Analysis

Found 5 projects in monorepo, 0 projects with changes.

📊 Quick Summary

Project	Total Size	Change
react-10k	5.7 MB	0
react-1k	825.4 KB	0
react-5k	2.7 MB	0
rome	984.3 KB	0
ui-components	2.1 MB	0

Generated by Rsdoctor GitHub Action

[github-actions]

📦 Binary Size-limit

Comparing 21a4788 to refactor: simplify export info types by removing MaybeDynamicTargetExportInfo (#12601) by harpsealjs

🎉 Size decreased by 4.13KB from 47.87MB to 47.87MB (⬇️0.01%)

[codspeed-hq]

CodSpeed Performance Report

Merging #12614 will not alter performance

_{Comparing 01-04-refactor/remove-helpers (21a4788) with main (6a1fbdd)}

Summary

✅ 16 untouched
⏩ 1 skipped¹

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩