Show deployments in UI

[anbraten]

Clear and concise description of the problem

I want to be able to see all active deployments of my branch.

Suggested solution

Add some tab / area to show all (active) deployments of a project. It would be nice to to be able to save one or multiple links per deyploment, so they could link to a review environment for example.

I see two options for setting these links:

• an official plugin which calls some api-endpoint setting that link
• some setting in the pipeline config file which allows to set a url like: ${DRONE_BRANCH_SLUG}.review.my-site.tld

Alternative

No response

Additional context

No response

Validations

• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[anbraten]

should probably be solved by #1006