fix(ci): use target repo default branch when -R flag is used in CI commands instead of local branch

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Description

• fix(ci): use target repo default branch when -R flag is used in CI commands instead of local branch

Fix works by detecting repo override: Check if the -R flag is used

Branching logic:

• If explicit branch (-b) is provided → use it
• If repo override (-R) is used → use target repo's default branch (ignore local branch)
• If no repo override → use local git branch (existing behavior)
• If no git repo → fallback to target repo's default branch
• Backward compatibility: The fix maintains full backward compatibility - existing usage without -R flag works exactly as before

Related Issues

Resolves #7957

How has this been tested?

• Added tests for new branch resolution functionality
• Tested locally by building CLI

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation
• Chore (Related to CI or Packaging to platforms)
• Test gap

Closes #7957