docs: update documentation (#25440)

* docs: beginning of the year tune up and updates

* darker dark

* backup information

* promote to table of content

* Apply suggestions from code review

Co-authored-by: Mert <101130780+mertalev@users.noreply.github.com>
Co-authored-by: Mees Frensel <33722705+meesfrensel@users.noreply.github.com>

* restore and backup

* edit

* Apply suggestions from code review

Co-authored-by: bo0tzz <git@bo0tzz.me>

* feedback

* more information on mobile

Co-authored-by: https://github.com/aviv926

* more information on free up space
>
> Co-authored-by: jtagcat <git-12dbd862@jtag.cat>

* Update docs/docs/features/mobile-app.mdx

Co-authored-by: jtagcat <git-12dbd862@jtag.cat>

* screenshot and minor tweaks

---------

Co-authored-by: Mert <101130780+mertalev@users.noreply.github.com>
Co-authored-by: Mees Frensel <33722705+meesfrensel@users.noreply.github.com>
Co-authored-by: bo0tzz <git@bo0tzz.me>
Co-authored-by: jtagcat <git-12dbd862@jtag.cat>

docs/docs/developer/setup.md

@@ -37,7 +37,8 @@ All the services are packaged to run as with single Docker Compose command.
 1. Clone the project repo.
 2. Run `cp docker/example.env docker/.env`.
 3. Edit `docker/.env` to provide values for the required variable `UPLOAD_LOCATION`.
-4. From the root directory, run:
+4. Install dependencies - `pnpm i`
+5. From the root directory, run:
 
 ```bash title="Start development server"
 make dev # required Makefile installed on the system.