feat(cli): update clara-companion command naming and add local/cloud selection

[esc247]

What Changed

This PR introduces two key improvements to the clara-companion CLI tool:

1. Local vs Cloud Authentication Selection

   • Users can now choose their authentication target when running clara-companion login
   • Options provided:
     • [1] Local Installation (localhost:3000) - For self-hosted deployments
     • [2] ClaraVerse Cloud (https://claraverse.app) - For cloud users
     • [3] Custom URL - For advanced configurations

2. Consistent Command Naming

   • Changed command name from clara_companion to clara-companion throughout the codebase
   • Updated all user-facing messages, help text, and documentation

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Why This Matters

• Self-hosted users can now easily configure the companion for their local installations without manual URL editing
• Consistent naming improves user experience and reduces confusion between the CLI tool name and internal references
• Better UX with clear, guided authentication flow

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How to Test

1. Build the CLI:

   cd backend/mcp-bridge
   go build -o clara-companion ./cmd/clara_companion

2. Run login command:

   ./clara-companion login

3. Verify the selection prompt appears:

   Server Connection
   
   Select authentication target:
   
   [1] Local Installation (localhost:3000)
   [2] ClaraVerse Cloud (https://claraverse.app)
   [3] Custom URL
   
   Choose (1/2/3) [1]:
   

4. Test each option:

   • Option 1 should configure ws://localhost:3000
   • Option 2 should configure wss://api.claraverse.app
   • Option 3 should prompt for custom URL

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Breaking Changes

None. This is a backward-compatible enhancement.

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Related Issues

Closes any issues related to local installation authentication configuration.

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Checklist

• Code follows project coding standards
• Commit message follows Conventional Commits format
• Documentation updated
• Changes tested manually
• Pushed to fork for PR review