feat(transformer): add ES2026 target for explicit resource management

[Boshen]

Summary

fixes #12796

• Added target ES2026
• Moves the explicit resource management feature from proposals to ES2026, as it is now a finalized ECMAScript 2026 feature.

🤖 Generated with Claude Code

[graphite-app]

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[Copilot]

Pull Request Overview

This PR moves the explicit resource management feature from the proposals module to ES2026, reflecting its finalization in the ECMAScript 2026 specification.

• Creates a new ES2026 module structure with options and transformer implementation
• Updates the transformer to use ES2026 instead of proposals for explicit resource management
• Cleans up the proposals module by removing the explicit resource management code

Reviewed Changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/oxc_transformer/src/proposals/options.rs	Removes explicit_resource_management field and simplifies ProposalOptions
crates/oxc_transformer/src/proposals/mod.rs	Removes explicit resource management module imports
crates/oxc_transformer/src/options/mod.rs	Updates BabelOptions integration to use ES2026Options
crates/oxc_transformer/src/options/env.rs	Adds ES2026Options to EnvOptions with explicit resource management support
crates/oxc_transformer/src/lib.rs	Replaces proposals-based transform with ES2026 module integration
crates/oxc_transformer/src/es2026/options.rs	Defines ES2026Options with explicit resource management field
crates/oxc_transformer/src/es2026/mod.rs	Implements ES2026 transformer with explicit resource management support

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #14330 will not alter performance

_{Comparing feat/move-explicit-resource-management-to-es2026 (588acd5) with main (81a28d4)}

Summary

✅ 37 untouched

[Boshen]

Merge activity

• Oct 5, 3:32 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Oct 5, 7:12 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Oct 5, 7:18 AM UTC: Merged by the Graphite merge queue.