[Docs] Better surface filecoin pin

[BigLep]

Done Criteria

1. Add an entry for filecon-pin CLI and upload action
2. Explain that this is about providng FOC affordances for the IPFS community
3. Make the hyperlinks more clear. The only link to pin.filecoin.cloud is the screenshot.

Why Important

Drive awareness and traffic to tooling we have invested a lot of time into that may meet a user's needs.

Notes

1. I'm assuming this improved content will live at https://docs.filecoin.cloud/resources/community-projects/#filecoin-pin