Fix: Makes service alert scrollable and fix text color

[HossamSaberr]

Hi, I'm new to open-source contributions and I've been working on a fix for this issue.

This pull request fixes #1454 by:

1. Scrolling: Adding code to SituationDialogFragment.java to set a max height on the ScrollView. This makes the dialog scrollable when the alert text is very long.
2. Text Color: Updating SituationDialogFragment.java to manually check for dark/light mode. This sets the text color to BLACK (in light mode) or WHITE (in dark mode) so it's always readable.
3. Background Color: Updating situation.xml to use a theme-aware background (?android:attr/colorBackground) so it also respects light/dark mode.

I tested this on my device by creating a fake alert, and it seems to solve the issue. I hope this helps!

---

• Apply the AndroidStyle.xml style template to your code in Android Studio.
• Run the unit tests with gradlew connectedObaGoogleDebugAndroidTest to make sure you didn't break anything
• If you have multiple commits please combine them into one commit by squashing them for the initial submission of the pull request.

Note: I am not using Android Studio, so I was unable to apply the AndroidStyle.xml template. I ran the connected tests successfully and manually tested the fix by building the APK and installing it on my phone.

[CLAassistant]

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