Add progress after a pull-request for a recipe

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We should add clear documentation describing what happens after a contributor creates a new recipe, submits a pull request, and gets it accepted.

This should include:

1. A link to dash (our builder system)
2. An explanation that the package is first built and published in volatile
3. Guidance on how contributors can track the build and publication progress there

From there, document the full lifecycle:

1. Recipe is accepted (PR merged)
2. Package is built in our build system
3. It appears in the volatile repository
4. It eventually moves from volatile → “stable” repository

This gives new contributors a complete end-to-end view of what happens after their contribution is merged, including how to follow their package through each stage.