SX-UI: offchain proposal editor

Framing

We should reuse, to the extent possible, the same UI components used for onchain voting.
We’ll enforce a common voting delay and voting period across the space’s proposals, so there’s no need to show options for that within the proposal editor.
In the case of offchain space proposals, we will need to add a dropdown for selecting voting type (basic, single choice, approval).
- If type is not basic, then we will need a way to add choices
- Designer’s input will be needed to implement this part (below is just for reference).

You can test here on second step of proposal creation:

I recommend starting with just basic voting (For, Against, Abstain) as that's voting types we support right now -> we will likely need some design input for both editor and voting part).
We will need remove this check so we can access editor: https://github.com/snapshot-labs/sx-monorepo/blob/5279ba93d606c5744891307509eb0e3906b1c1e9/apps/ui/src/views/Space/Overview.vue#L66
Editor checks for VP before user can create proposal. SX spaces have separate strategies for voting and proposing (I'm not familiar with Snapshot v1) - we will need to fill in proper strategies there (to either use the same, or different values if Snapshot v1 has different strategies for proposing as well) - will need to adjust types to make sense: https://github.com/snapshot-labs/sx-monorepo/blob/75315e017c7361c93ef7d5a8d5303f5fc3ef4351/apps/ui/src/networks/offchain/api/index.ts#L75-L77
Next step will be to add propose method (remember to change useActions to use getNetwork instead of getReadWriteNetwork for propose), similar to vote and add support to propose method in sx.js (similar as vote). https://github.com/snapshot-labs/sx-monorepo/blob/737bfe872936f8372490a56aae109075a56c7c9d/apps/ui/src/networks/offchain/actions.ts#L32-L52