Fixed cursor jumping to end issue

[tusharonly]

PR Description

Fixed cursor jumping to end issue in URL text field. When editing a character in the middle of the URL, the cursor would automatically move to the end, making it difficult to edit URLs.

Root Cause: The didUpdateWidget method in EnvironmentTriggerField was recreating the TextEditingController on every text change, always positioning the cursor at the end.

Solution: Modified the controller update logic to:

• Preserve the current cursor position when text is updated from user input
• Only reset cursor to end when switching between different requests (keyId changes)
• Ensure cursor position stays within valid bounds using .clamp(0, newText.length)
• Avoid unnecessary controller updates when text hasn't actually changed

Related Issues

• Closes Typing or Removing any character in between URL textfield moves the cursor to the end unexpectedly. #924

Checklist

• I have gone through the contributing guide

• I have updated my branch and synced it with project main branch before making this PR

• I am using the latest Flutter stable branch (run flutter upgrade and verify)

• I have run the tests (flutter test) and all tests are passing

Added/updated tests?

We encourage you to add relevant test cases.

• No, and this is why: This is a UI interaction fix that addresses cursor positioning behavior. The existing tests continue to pass and validate the text field functionality. Additional widget tests for cursor position preservation could be added in a future enhancement.

OS on which you have developed and tested the feature?

• Windows

• macOS

• Linux