Docs: caught up with v0.13.0 to v0.19.0

The documentation had kept up feature page by feature page and nowhere
else. Now also:

- the home page's App cards (notes of any size, pictures, sharing) and its
  note (the Shell, the VPN, the screenshot key);
- the guide: VPN in the Status Bar and in Settings, the three keys that work
  everywhere, screenshots of the Shell, a picture, sharing, the VPN page and
  the help panel;
- three how-tos: move files with your phone, set up the VPN, take a
  screenshot; where the files are and what things cost in memory;
- the FAQ: screenshots, and what listens on the network;
- the README's opening: what the firmware does today;
- the glossary: Tunnel, Sharing, Screenshot;
- every milestone's status line, with the version each thing shipped in.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

site/content/howto/phone-files.md

@@ -0,0 +1,30 @@
++++
+title = "Move files with your phone"
+description = "Open the SD card in your phone's browser, over Wi-Fi: download what the device wrote, upload what it needs. Nothing to install."
+weight = 9
+[extra]
+tag = "SD card"
++++
+
+The phone and the Cardputer must be on the **same Wi-Fi network**.
+
+1. On the Cardputer, open **Storage** and press <kbd>w</kbd>. You should see a QR code, an address and a six-digit code.
+2. On the phone, **scan the QR code** with the camera and open the link. The page opens on the card's folders. (Without a camera: type the address in a browser, then the code.)
+3. **To download:** tap a folder to go in, tap a file to download it.
+4. **To upload:** go to the folder you want, tap **Upload files** and pick one or several. A bar shows the progress; if a file with that name is there already, the page asks before replacing it.
+5. **New folder** and **Delete** do what they say. A folder must be empty to be deleted.
+6. On the Cardputer, press Back. Sharing stops, and the code is no longer good.
+
+## What to expect
+
+- About **200 KB a second**: a 3 MB photo takes a quarter of a minute.
+- **One thing at a time.** While a big file moves, the page waits.
+- The device's screen shows how much has gone in and out, and the last thing that was asked.
+
+## Good to know
+
+- **It is not encrypted.** Use it on a network you trust, or [through the VPN](/guide/vpn/).
+- Five wrong codes close it for a minute.
+- It works from a computer's browser too.
+
+More in [Storage: From a phone](/guide/storage/#from-a-phone).