Remove throttle on pty input

[Tyriar]

See microsoft/node-pty#831 for a detailed write up on the cause and solution.

Fixes #283056
Fixes #246204

cc @deepak1556

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After test by pasting 50kb of data takes ~500ms - the reason that this is not instantaneous would likely require moving all writing to the fd into C++ (microsoft/node-pty#833):

After test ensure EAGAIN is correctly handled by pasting > 1kb during a shell sleep:

[Copilot]

Pull request overview

This PR removes the throttling mechanism for PTY input handling in the terminal process, simplifying the input flow by eliminating queuing and delayed writes. The changes directly write input to the PTY process instead of chunking and throttling writes through a queue system.

Key Changes

• Removed the chunkInput() utility function that split large input into smaller chunks (max 50 characters) to prevent data corruption
• Simplified the input() method to write directly to the PTY process instead of using a write queue with 5ms intervals
• Removed supporting infrastructure including _writeQueue, _writeTimeout, _startWrite(), and _doWrite() methods

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/vs/platform/terminal/node/terminalProcess.ts	Removed import of chunkInput, removed queue-related fields and methods (_writeQueue, _writeTimeout, _startWrite(), _doWrite()), and simplified input() method to write directly to PTY process
src/vs/platform/terminal/common/terminalProcess.ts	Removed chunkInput() utility function and related constants that were used to split large input into chunks