feat(workspaces): add multi-repository workspace management

[CalvinAllen]

Description

Add workspace functionality for organizing and managing multiple Git repositories as logical groups, improving workflow for projects spanning multiple repos.

Features

Workspace Management

• Create named workspaces
• Add repositories to workspace
• Remove repositories from workspace
• Rename workspaces
• Delete workspaces
• Import/export workspace definitions

Workspace Types

• Local Workspaces - Stored locally, machine-specific
• Cloud Workspaces - Synced across devices (optional cloud service)
• Solution-linked - Auto-detect repos in solution folder

Workspace View

• List all workspaces
• Expand to see repositories in each
• Repository status indicators (clean/dirty/ahead/behind)
• Quick actions per repository
• Bulk operations on workspace repos

Repository Actions (Per Workspace)

• Fetch all repositories
• Pull all repositories
• View combined status
• Open repository in new window
• Remove from workspace

Auto-Discovery

• Scan folder for Git repositories
• Add all repos in solution
• Smart detection of related repos

Workspace Definition

{
  "name": "My Project",
  "repositories": [
    { "path": "C:/repos/frontend", "name": "Frontend" },
    { "path": "C:/repos/backend", "name": "Backend" },
    { "path": "C:/repos/shared", "name": "Shared Libs" }
  ]
}

Configuration Options

• Default workspace location
• Auto-detect repositories toggle
• Cloud sync settings (if applicable)
• Workspace file format

Related Issues

• feat(repo): add repository management features #10 - Repository management features (single-repo management that this extends to multi-repo)

Note: This feature extends the single-repository management capabilities from #10 to support multiple repositories organized into workspaces. Individual repository features from #10 apply to each repo within a workspace.

Acceptance Criteria

• Workspaces can be created and managed
• Repositories can be added/removed
• Workspace view displays all workspaces
• Bulk operations work across repos
• Auto-discovery finds repositories
• Import/export functions correctly