[Docs] Ente help on local indexing and notifications (#6226)

## Description

- Add some info on (disabling) local indexing
- Add some info on notifications

## Tests

docs/docs/.vitepress/sidebar.ts

@@ -52,6 +52,10 @@ export const sidebar = [
                         link: "/photos/features/machine-learning",
                     },
                     { text: "Map", link: "/photos/features/map" },
+                    {
+                        text: "Notifications",
+                        link: "/photos/features/notifications",
+                    },
                     {
                         text: "Passkeys",
                         link: "/photos/features/passkeys",

docs/docs/photos/features/machine-learning.md

@@ -47,8 +47,20 @@ device.
 The indexes are synced across all your devices automatically using the same
 end-to-end encrypted security that we use for syncing your photos.
 
-Note that the desktop app does not currently support modifying the face
-groupings, that is only supported by the mobile app.
+---
+
+#### Local indexing on mobile
+
+In general the machine learning is optimized to work well on most mobile device.
+However, devices with low RAM (4-6GB) and large photo libraries might struggle
+to complete the indexing without affecting performance of the app. In such case,
+you might want to disable local indexing and let the desktop run it instead.
+
+You can disable local indexing from the settings, under
+`General > Advanced > Machine learning > Configuration`. This way, you can
+continue to use the ML features without your phone performance taking any hit.
+
+---
 
 For more information on how to use Machine Learning for face recognition please
 check out [the FAQ](../faq/face-recognition).

docs/docs/photos/features/notifications.md

@@ -0,0 +1,33 @@
+---
+title: Notifications
+description: Details about notifications in Ente
+---
+
+# Notifications
+
+The Ente app can send notifications to notify you of an update, or just to
+remind you of some sweet or helpful memory at the right time.
+
+## New shared photos
+
+Receive notifications when someone adds a photo to a shared album that you're a
+part of.
+
+## "On this day" memories
+
+Receive reminders about memories from this day in previous years. These
+reminders will only be shown if there are enough photos taken across previous
+years of the specific day.
+
+## Birthday notifications
+
+Receive reminders when it's someone's birthday. Tapping on the notification will
+take you to photos of the birthday person. This requires you to first add a
+birthday to a person, and will only be shown if there are enough photos of that
+person.
+
+## Notification permission
+
+By default all notification categories are enabled if you give notification
+permission. You can disable all of the above notification categories from
+`Settings > Notifications`. Notifications currently only work on mobile.