Add project — dropdown & both flows

The folder-open button next to New task opens a two-option dropdown. “Open local folder” browses the server's home dir via GET /api/fs/browse; “Clone from GitHub” runs gh repo clone into the global checkout root (~/cezar/projects/<name>) and is disabled with a reason when gh is unavailable.

📁
Open local folder…
Register a folder that's already on this machine
⧉
Clone from GitHub…
Check out a repository into ~/cezar/projects
Open local folder
Pick the folder cezar should run in. Git repos are marked; any folder works.
~ / Projects
📁..
📁cezaralready added
📁shop-frontendgit
📁open-mercatogit
📁notes
📁experiments
/Users/piotr/Projects/shop-frontend
Clone from GitHub
Checked out with gh using your existing login.
Will clone into ~/cezar/projects/shop-backend — change the root in Global settings.
Cloning… receiving objects 64%
gh authenticated as piotrkarwatka