Bump version to 0.2.4, document SQL query mode, add Russian README

README.md

@@ -1,5 +1,7 @@
 # ⚠️ Deprecated ⚠️ OCCWeb terminal
 
+*Читать на [русском](README.ru.md).*
+
 ### A web terminal for admins to launch Nextcloud's occ commands
 
 ![occweb](https://github.com/Adphi/OCCWeb/raw/main/appinfo/screenshot.png)
@@ -14,6 +16,19 @@ As nextcloudd has no native support for asynchronous operations, due to the use
 
 Place this app in **nextcloud/apps/**
 
+## SQL query mode
+
+Type `sql` in the terminal to switch into SQL query mode and run raw SQL
+statements directly against the Nextcloud database (admin only). Separate
+statements with `;`. Use **Shift+Enter** to add a new line and **Enter** to
+run the whole block in a single request — this matters for scripts like
+`SET vars.x = 'value'; SELECT current_setting('vars.x');`, since every
+statement in one submission runs on the same database connection/session.
+Type `occ` to switch back to the normal occ-command mode.
+
+⚠️ There is no undo for `DELETE`/`UPDATE` statements — double check what
+you are about to run, ideally against a non-critical row/user first.
+
 ## ⚠️ Warnings ⚠️
 
 - The application is not a real interactive terminal and does not support long running tasks.