feat(@angular/build): migrate advanced optimization Babel plugins to oxc-parser + magic-string

[clydin]

This change ports the remaining Babel plugins used for Angular build optimizations to a single unified, ultra-fast oxc-transform pass using oxc-parser and magic-string.

Optimization passes migrated:

• TypeScript Enum wrapping
• Class static members elision and wrapping
• Angular metadata elision (setClassMetadata, etc.)
• Top-level pure function call and constructor annotation

For regular optimized builds, this bypasses Babel entirely. For builds with code coverage or linking, it runs Babel first and then processes the output through the new fast path.

[gemini-code-assist]

Code Review

This pull request introduces a fast, single-pass AST-based transformation (oxc-transform.ts) using oxc-parser and magic-string to replace Babel for advanced optimizations, including TypeScript enum wrapping, static class member elision/wrapping, Angular metadata elision, and top-level pure function annotations. It integrates this new transformer into the JavaScript transformer worker and adds comprehensive test suites. The review feedback highlights opportunities to improve robustness and performance, such as using strict regex checks for numeric suffixes, adding defensive checks for array expression elements, supporting empty static blocks, removing unused variables and imports, and extracting metadata function names into a static Set to avoid repeated array allocations.

[clydin]

This PR was merged into the repository. The changes were merged into the following branches:

• main: 10dc30f