feat: send screen recordings (#128)

* first pass implementation

* remove screenrecord shortcut hint

* refactor

* fix: prevent mirror review of screen recording

* feat: allow recording with webcam overlay

* fix: review screen recording without clipped content

* tidy keyboard hints consistent position

* refactor: re-use one component for screen picker

huddles and screen clips use same picker component now. We had to make
sure that tailwind works for both of them.

* fix: improve visibility of keyboard hints

During compose video or screen recording, the keyboard hints were
invisible if the content was super bright.

js/src/electron.d.ts

@@ -30,6 +30,16 @@ declare global {
       onStop: (callback: () => void) => () => void;
       onNavigate: (callback: (data: { networkId: string; streamId: string }) => void) => () => void;
     };
+    electronScreen: {
+      getScreenSources: () => Promise<ScreenSource[]>;
+      startRecordingWindow: (data: { includeCamera: boolean }) => void;
+      stopRecordingWindow: () => void;
+      onStopRequested: (callback: () => void) => () => void;
+    };
+    electronScreenRecord: {
+      stop: () => void;
+      onInit: (callback: (data: { includeCamera: boolean }) => void) => () => void;
+    };
     electronLink: {
       fetchMetadata: (url: string) => Promise<LinkMetadata | null>;
       openExternal: (url: string) => Promise<void>;