Fix WSL2 web login hanging issue by improving browser opening fallback

[gajeshbhat]

Description

Fixes the issue where jf config add hangs indefinitely on WSL2 when using "Web Login" authentication method.

Problem

In WSL2 environments, the browser.OpenURL() function fails because there's no default browser configured. The original code treated this as a fatal error and exited immediately, causing the CLI to appear to hang since users never saw the authentication URL.

Solution

• Always display the authentication URL prominently before attempting browser opening
• Continue on browser failure instead of exiting, allowing manual authentication
• Add WSL2-specific environment variable support:
  • BROWSER=none - Disables automatic browser opening
  • JFROG_CLI_BROWSER_COMMAND - Allows custom browser command (e.g., Windows browser from WSL2)
• Provide clear user guidance with WSL2-specific instructions

Changes

• Modified utils/coreutils/coreconsts.go to add browser command environment variable
• Enhanced artifactory/utils/weblogin.go with improved browser opening logic
• Added comprehensive unit tests in artifactory/utils/weblogin_test.go

Testing

• Added unit tests covering all new functionality
• Tested environment variable support
• Verified graceful error handling scenarios

WSL2 Usage Examples

# Disable browser opening
export BROWSER=none
jf config add my-server --url=https://company.jfrog.io

# Use Windows Chrome from WSL2
export JFROG_CLI_BROWSER_COMMAND="/mnt/c/Program Files/Google/Chrome/Application/chrome.exe"
jf config add my-server --url=https://company.jfrog.io

Closes

Fixes jfrog/jfrog-cli#3008

Files Summary:

• 2 files modified and 1 new unit test file added
• Backward compatible - existing functionality unchanged
• WSL2-specific improvements without affecting other platforms
• Comprehensive test coverage for new functionality

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[gajeshbhat]

I have read the CLA Document and I hereby sign the CLA

[gajeshbhat]

recheck

[gajeshbhat]

Closing this Pull request for now. I think the workaround should be sufficient for now.