FEATURE - implement realtime alert functionality

[OmarHegazy93]

What it Does

Wire the implemented UI for realtime alert system with the server so that it gets updated each time new alert is arrived

• Closes FEATURE - Create a Real Time Alert System #107
• Describe what your change does
  Add functionality to realtime alert system by:

1. listening to the server for newly added alerts
2. Add a query to get only ONE alert with isOn: true, and if there are viewed alerts previously, append to the query to exclude all alerts that ids match the persisted ids
3. if the alert is new, present it and save its id locally so that it gets filtered next time when new alerts are received

How I Tested

• Install the app and run it for the first time
• An alert should appear on the screen
• Dismiss it
• Reopen the app
• Notice the behavior

Notes

• When running the app for the second time, there will be an error from the firebase in the console as shown in the screenshot below, as per the answer here, @mikaelacaron should open that link so that it gets created automatically afterwards. (please let me know if there is something else I should do about it)

Screenshot

• Add a screenshot of your new feature! OR show a screen recording of it in action. (On the simulator press Cmd + R to record, and the stop button when done). This video should be no longer than 30 seconds.

[mikaelacaron]

I haven't fully looked at it functionality wise, if it works (and testing with Firebase, so I'm not sure yet on the question you had about that error)

But here's several suggestions to please fix, and I'll take a look again
Great work again!! You're doing awesome!

[mikaelacaron]

Great work!! Note I pushed several changes (so you'll need to do git pull on your branch)
Mainly just formatting changes here and there.

Added those indexes for alerts

I have a few questions. Otherwise this will be good to merge soon!

And can you make sure that the title doesn't get clipped when it's longer (see screenshot) and make sure in the message when I add \n for a line break, that it shows up as a line break

[mikaelacaron]

showing \n\n rather than as line breaks

the title is clipped

[mikaelacaron]

The code looks good but I haven't been able to test it successfully with the functionality that I'm wanting.

I'm going to accept it, and look at it again after Hacktoberfest, or put it behind a feature flag for now, thanks for all your work on this!