feat(tasks/compat_data): add custom compat data for export namespace from

[sapphi-red]

Added a way to add custom compat data that doesn't exist in compat table. Also added the data for "export namespace from".

[sapphi-red]

• feat(tasks/compat_data): add custom compat data for export namespace from #14317 : 2 dependent PRs (#14276 , #14277 ) 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #14317 will not alter performance

_{Comparing 10-03-feat-compat-add-custom-compat-data-for-export-namespace-from (be53dad) with main (34e1c0b)}

Summary

✅ 33 untouched
⏩ 4 skipped¹

Footnotes

1. 4 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull Request Overview

This PR adds support for custom compatibility data that doesn't exist in the compat-table by creating a new infrastructure for manually maintained browser support information. The key change is the addition of compatibility data for the "export namespace from" ES2020 feature.

• Creates a custom compatibility data system for features not in compat-table
• Adds specific browser version support data for "export namespace from" syntax
• Integrates custom data into the build process alongside existing compat-table data

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
tasks/compat_data/custom-compat-data.js	New file defining custom compatibility data structure and ES2020 export namespace from support
tasks/compat_data/build.js	Integrates custom compatibility data into the build process
tasks/compat_data/data.json	Generated output containing the new ExportNamespaceFrom compatibility data
crates/oxc_compat/src/es_features.rs	Adds ES2020ExportNamespaceFrom enum variant and corresponding engine targets

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