Align Flow lib defs for Node.js buffer with v24

[robhogan]

Summary:
This is an AI-assisted change to align the Flow definitions for the buffer module with the Node.js docs as at v24.

New Validation Functions:

1. isUtf8(input) - UTF-8 validation (added in v19.4.0, v18.14.0)

   • Validates if Buffer/ArrayBuffer/TypedArray contains only valid UTF-8 data
   • Returns true for valid UTF-8 (including empty buffers)
   • Throws error if input is a detached array buffer
   • https://nodejs.org/api/buffer.html#bufferisutf8input

2. isAscii(input) - ASCII validation (added in v19.6.0, v18.15.0)

   • Validates if Buffer/ArrayBuffer/TypedArray contains only ASCII (0x00-0x7F)
   • Returns true for valid ASCII (including empty buffers)
   • Throws error if input is a detached array buffer
   • https://nodejs.org/api/buffer.html#bufferisasciiinput

Blob URL Resolution:

3. resolveObjectURL(id) - Resolve Blob from URL (added in v16.7.0)
   • Resolves 'blob:nodedata:...' URL to its associated Blob object
   • Returns Blob or undefined if URL not found
   • Works with URLs created via URL.createObjectURL(blob)
   • https://nodejs.org/api/buffer.html#bufferresolveobjecturlid

New Constants:

4. constants object - Buffer size limits
   • constants.MAX_LENGTH - Maximum size of a single Buffer instance
   • constants.MAX_STRING_LENGTH - Maximum length for string operations
   • https://nodejs.org/api/buffer.html#bufferconstantsmax_length

Web API Classes (re-exported):

5. Blob class - Exported from buffer module (global in v18.0.0)

   • Web API-compatible Blob for immutable binary data
   • Also available as global (no import needed in v18+)
   • https://nodejs.org/api/buffer.html#class-blob

6. File class - Exported from buffer module (global in v20.0.0)

   • Web API-compatible File extending Blob
   • Also available as global (no import needed in v20+)
   • https://nodejs.org/api/buffer.html#class-file

References:

• Node.js buffer module docs: https://nodejs.org/api/buffer.html

Changelog: [Internal]

Generated by Confucius Code Assist (CCA)
Confucius Session, Trace

Reviewed By: vzaidman

Differential Revision: D89942832

[meta-codesync]

@robhogan has exported this pull request. If you are a Meta employee, you can view the originating Diff in D89942832.

[meta-codesync]

This pull request has been merged in 4862cc7.

[react-native-bot]

This pull request was successfully merged by @robhogan in 4862cc7

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