Sourcegraph CEO here. There are a ton of keyboard shortcuts, and they (mostly) match VS Code's default ones. To see them all, hit Shift+Cmd+P (or Shift+Ctrl+P), and go to 'Preferences: Open Keyboard Shortcuts'.
Here are some of the key (no pun intended) ones:
Opt+S: Open QuickOpen (omni-search: searches files, workspace symbols, and repos) - Cmd-P and F1 also work