feat(Dialog): add programmatic close functionality to dialog root

[JosephAnson]

🔗 Linked issue

I've made this PR to help support the change to NuxtUI, as it would reduce the amount of internal state needed: nuxt/ui#4219

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Implemented programmatic close method for DialogRoot component.

New Feature:

• Programmatic close method - Modal now exposes a close method through the #default scoped slot, allowing dialogs to be closed from within their content without requiring external ref management.

Documentation Updates:

• Shows how to eliminate the need for manual v-model:open ref management.

Benefits:

• No need to create and manage boolean refs for modal state
• Reduces boilerplate code and cognitive load

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/reka-ui@1943

commit: 2a3dcd1

[zernonia]

Thanks for the PR @JosephAnson ! Simple and straightforward!