feat: add cancelability section

docs/concepts/protocol/10-cancelability.md

@@ -0,0 +1,56 @@
+---
+id: "cancelability"
+sidebar_position: 10
+title: "Cancelability"
+---
+
+## Streams
+
+When creating a Sablier stream, users have the ability to set the stream as cancelable, or uncancelable.
+
+If **cancelable**, the stream can be stopped at any time by the stream creator, with the unstreamed funds being returned
+over to the stream creator.
+
+**Example:** If you are using Sablier to pay your employees, and one of your employees leaves your company, you can
+cancel the stream and get the funds back which haven't yet been paid out to the ex-employee at that specific time. Any
+funds paid out before that are obviously now owned by the recipient.
+
+:::info
+
+When a stream is canceled (stopped), there is no way to uncancel it (start it again). You will need to create a new
+stream in that case.
+
+:::
+
+If **uncancelable**, there is no way to cancel the stream, and the recipient is guaranteed to receive the funds.
+
+A cancelable stream can be set as uncancelable at any point in time by the stream creator. On the other hand, an
+uncancelable stream cannot be set as cancelable by the stream creator.
+
+Recipients do not have the ability to cancel a stream.
+
+## Airstream campaigns
+
+If you have created an Airstream campaign and made a mistake, you can recover the funds from the campaign that haven't
+yet been claimed in the following cases:
+
+- Before any user claimed from the campaign
+- Up until 7 days after the first claim took place
+- After the claim window ends (assuming it's enabled)
+
+If you haven't set up a claim window, you can only recover the funds you deposited into the Airstream campaign up until
+7 days after the first claim took place, or as long as you like if there are no claims. Assuming there are claims, after
+the 7-day period passes, you will not have the ability anymore to recover the funds deposited into the campaign
+contract. They will stay there forever until claimed by eligible recipients.
+
+If you have set up a claim window, after the claim window ends, you have the ability to get the funds back which haven't
+yet been claimed by that time.
+
+It's important to mention that the streams created through the Airstream campaign can be set as cancelable, the above
+points are related to the campaign itself, not the streams created through users claiming from the campaign.
+
+**Example:** you create an Airstream campaign. You deposit 1000 USDC in it. You set up the streams as cancelable, but
+there is no claim window. All eligible users claim from the campaign at the same time, and 8 days later, you realize you
+made a mistake. While you cannot recover the funds through the campaign as the 7-day period has passed, you can cancel
+the streams that were created and get the funds back which haven't been paid out at that specific time to the
+recipients.