Add Contract & Uniswap listing

[bedeho]

Add somethign to top menu, link to uniswap page.

Waiting for input from @kdembler

[leetjoy]

I propose to add information about wrapped JOY, bridge, contract address and Uniswap widget itself to /token page:

1. Similar to ChangeNow field but for Uniswap aka Instantly Buy or Sell JOY on BASE + Uniswap Widget (https://docs.uniswap.org/sdk/swap-widget/guides/getting-started)
   
   Content:
   Link to Argo Bridge app: https://bridge.joystream.org/
   Link to Uniswap itself: https://app.uniswap.org/swap?chain=base&inputCurrency=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913&outputCurrency=0x8761155c814c807cD3CcD15B256D69D3C10f198C
   Smart contract address 0x8761155c814c807cD3CcD15B256D69D3C10f198C
   Link to blog: https://blog.joystream.org/joystream-bridges-introducing-argo/

2. Add Uniswap to "Where can you buy and sell JOY?"
   

[bedeho]

Good idea, then top menu button can just link to this swap section.