Add-Tdarr node to Docs

[RaneyDazed]

Added tdarr node reference to index.md, mkdocs.yml, and created the docs page.

• [x] App documentation page created
• [x] Reference added in sandbox/index.md
• [x] Reference added in mkdocs.yml

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[owine]

This isn't correct for node. There is not a web interface. Better would be to document how to reach the node from another machine running tdarr

[RaneyDazed]

Ok, i thought I'd leave the tdarr url bit there for tdarr itself. But idk how to use tdarr. Maybe I should close it and let someone document it more on the tdarr page instead?