Add support for app shortcuts

[anaestheticsapp]

• Add shortcuts to manifest.json
• Available in Chrome 84 for Android (only working via TWA at the moment)
• Behind a flag on Windows in Chrome 84 and Edge 84 (won't redirect to correct page due to browser bug)
• https://web.dev/app-shortcuts/

[anaestheticsapp]

App shortcuts enhance your productivity by allowing easy access to frequently used tasks from anywhere the app icon is displayed. Currently, this only works if you have installed the logbook from the Google Play Store. To view app shortcuts, long press the logbooks's launcher icon on your home screen.

We have currently added the following shortcuts:

• New theatre case
• New critical care case
• New event
• Logbook summary

Microsoft and Google are working on introducing app shortcuts for Windows, Mac OS and Chrome OS.