Test: Add unit tests for new command packages

[rbansal42]

Overview

The new command packages added in Phase 5a lack unit tests:

• internal/cmd/workspace/
• internal/cmd/project/
• internal/cmd/branch/

Tests to Add

Workspace Commands

• Test command registration
• Test flag parsing, output formatting
• Test --web behavior

Project Commands

• Test flag parsing, required --workspace validation
• Test required args validation

Branch Commands

• Test flag parsing, repo detection
• Test confirmation prompt, --force behavior

Reference

Follow patterns from existing command tests:

• internal/cmd/pr/pr_test.go
• internal/cmd/repo/repo_test.go

Acceptance Criteria

• Add tests for workspace commands
• Add tests for project commands
• Add tests for branch commands
• Achieve reasonable coverage (>70%)