Git Duplicate Branch Validation Before Command Execution

[batsev]

Currently in VS Code, when creating a Git branch, if a branch with the same name already exists, the command fails after execution, requiring the user to re-run the command with a different branch name. This is inefficient and frustrating, especially when compared to IDEs like IntelliJ IDEA, which validate branch names before executing the command.

Describe the solution you'd like
I would like VS Code to implement a pre-execution validation check for Git branch creation. Before running the command, VS Code should check if a branch with the same name already exists and notify the user immediately, preventing the need to re-run the command.

Describe alternatives you've considered
An alternative would be to manually check for existing branches using git branch --list before running the command, but this is cumbersome and defeats the purpose of having an integrated Git experience in VS Code.

Additional context
This feature is already available in IntelliJ IDEA, which provides a seamless experience by validating branch names upfront. Implementing this in VS Code would significantly improve the developer workflow and reduce frustration.