[docs] Add a misc FAQ page (#5402)

docs/docs/.vitepress/sidebar.ts

@@ -142,6 +142,7 @@ export const sidebar = [
                         text: "Video streaming",
                         link: "/photos/faq/video-streaming",
                     },
+                    { text: "Misc", link: "/photos/faq/misc" },
                 ],
             },
             {

docs/docs/photos/faq/misc.md

@@ -0,0 +1,20 @@
+---
+title: Miscellaneous general FAQ
+description: Unsorted frequently asked questions about Ente Photos
+---
+
+# Miscellaneous FAQ
+
+## Exif Description
+
+Ente will try to read as much information from Exif when the image is uploaded,
+but after that, only the fields which have been parsed into Ente can be
+searched.
+
+The app still show all the fields in the raw Exif data in the file info panel
+when someone taps on the "View all Exif" option, but otherwise the app is
+unaware of these fields.
+
+In particular, for the description associated with a photo, the exact logic to
+determine the description from the Exif when uploading the image can be seen
+[in this part of the code](https://github.com/ente-io/ente/blob/0dcb185744da469848b41b668fe4b647226b6fe2/web/packages/gallery/services/exif.ts#L609-L620).