chore(strings): Remove 49 unused string resources

None of these are referenced from any source set: a fixed-string grep over
app/src (Kotlin, Java, XML including the manifest, excluding res/values*)
finds zero hits for each, and the app has no getIdentifier-style dynamic
resource lookup, so nothing can reach them by name at runtime.

43 lost their last usage in an identifiable commit, mostly the Compose
migration (63692595), the upgrade/billing rework (c072b908, 3651bb3d,
e35bce4d, abb189f4) and the device-settings card grouping (65a74e9b,
32ff7e5b, 8a3a6cad). The other 6 were never referenced at all after the
commit that added them: debug_debuglog_recording_progress,
troubleshooter_ble_result_failure_body,
profilessettings_maindevice_identitykey_description,
profiles_maindevice_encryptionkey_description, pods_dual_left_short_label
and pods_dual_right_short_label.

Removed from the three base files and from all 75 locale files each, so a
Crowdin pull does not reintroduce them.

app/src/foss/res/values-fil/strings.xml

@@ -1,8 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <string name="foss_upgrade_donate_label">Mag-donate</string>
-    <string name="foss_upgrade_alreadydonated_label">Nakapag-donate na ako</string>
-    <string name="foss_upgrade_no_money_label">Ginagastos ko lahat ng pera ko sa AirPods</string>
     <string name="upgrade_foss_preamble">Ang CAPod FOSS ay libre at open source. Kung nakita mong kapaki-pakinabang ito, isaalang-alang ang pag-sponsor ng development para mapanatiling aktibo ang proyekto.</string>
     <string name="upgrade_foss_sponsor_action">Mag-sponsor ng development</string>
     <string name="upgrade_foss_sponsor_subtitle">Walang ads. Walang tracking. Walang Google Play lock-in.</string>