docs: update guidelines for Svelte module changes and linting requirements

- Enhanced documentation in AGENTS.md and web/README.md to clarify the mandatory steps for running `npm run check` and `npm run lint` before finalizing changes in the `web/**` directory.
- Updated engineering rules in .cursor/rules/engineering.mdc to specify the necessity of both commands and the use of Prettier for formatting issues.
- Added detailed instructions for handling linting failures and emphasized the importance of these checks in CI workflows.

web/README.md

@@ -21,8 +21,21 @@ SvelteKit-приложение панели управления EvoBGP. Зап
 npm install
 npm run dev
 npm run check
+npm run lint          # prettier --check; обязательно перед PR (CI job web)
 ```
 
+Из корня репозитория (обе проверки как в CI):
+
+```powershell
+powershell -NoProfile -File scripts/lint-web.ps1
+```
+
+```sh
+sh scripts/lint-web.sh
+```
+
+При падении `lint`: `npx prettier --write .` в каталоге `web/`, затем снова `check` + `lint`.
+
 Добавление компонентов shadcn (из каталога `web/`):
 
 ```sh