fix: update skill installation command

[ozsay]

Description

This PR updates the skill installation command throughout the codebase to use the new npx skills add syntax instead of the deprecated npx add-skill command. The change affects both the README documentation and the CLI's project creation command to ensure users receive correct instructions for installing AI agent skills.

Related Issue

None

Type of Change

• 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 not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Other (please describe):

Changes Made

• Updated README.md to use npx skills add base44/skills instead of npx add-skill base44/skills
• Modified src/cli/commands/project/create.ts to use the new command syntax in the skill installation flow
• Updated error message in create command to reflect the correct command for manual installation

Testing

• I have tested these changes locally
• I have added/updated tests as needed
• All tests pass (npm test)

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (if applicable)
• My changes generate no new warnings
• I have updated AGENTS.md if I made architectural changes

Additional Notes

This change ensures consistency with the updated skills package API. The old add-skill command is being replaced by the new skills add command pattern. This is a straightforward command update that maintains backward compatibility since it only changes the invocation syntax, not the underlying functionality.

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_{🤖 Generated by Claude | 2026-02-01 00:00 UTC}

[github-actions]

🚀 Package Preview Available!

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Install this PR's preview build with npm:

npm i @base44-preview/cli@0.0.25-pr.162.e7a27e4

Prefer not to change any import paths? Install using npm alias so your code still imports base44:

npm i "base44@npm:@base44-preview/cli@0.0.25-pr.162.e7a27e4"

Or add it to your package.json dependencies:

{
  "dependencies": {
    "base44": "npm:@base44-preview/cli@0.0.25-pr.162.e7a27e4"
  }
}

• 📦 Preview Package: @base44-preview/cli@0.0.25-pr.162.e7a27e4
• 🔗 View this commit on GitHub

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_{Preview published to npm registry — try new features instantly!}

[claude]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.