Observe stream of translations in PagerActivity

[ahmedre]

This patch updates PagerActivity and the InlineTranslations
functionality to observe the list of translations as they are updated
from the database. This solves issues like translations not showing up
right when they are added without returning to the menu and coming back.
Fixes #2460.

[github-actions]

OLD: app-madani-debug.apk (signature: V1, V2)
NEW: app-madani-debug.apk (signature: V1, V2)

          │            compressed            │           uncompressed           
          ├───────────┬───────────┬──────────┼───────────┬───────────┬──────────
 APK      │ old       │ new       │ diff     │ old       │ new       │ diff     
──────────┼───────────┼───────────┼──────────┼───────────┼───────────┼──────────
      dex │  12.6 MiB │  12.6 MiB │ +1.9 KiB │    32 MiB │    32 MiB │ +5.6 KiB 
     arsc │   2.2 MiB │   2.2 MiB │      0 B │   2.2 MiB │   2.2 MiB │      0 B 
 manifest │   5.6 KiB │   5.6 KiB │      0 B │  27.1 KiB │  27.1 KiB │      0 B 
      res │   1.6 MiB │   1.6 MiB │      0 B │   1.8 MiB │   1.8 MiB │      0 B 
    asset │ 404.2 KiB │ 404.2 KiB │      0 B │ 678.6 KiB │ 678.6 KiB │      0 B 
    other │ 188.2 KiB │ 188.3 KiB │    +29 B │ 384.8 KiB │ 384.8 KiB │      0 B 
──────────┼───────────┼───────────┼──────────┼───────────┼───────────┼──────────
    total │    17 MiB │    17 MiB │   +2 KiB │    37 MiB │    37 MiB │ +5.6 KiB