Add phone call handling on the car screen

Incoming calls now show the caller (name via contacts, else number) on
the car UI with answer/decline, using a call screening service so the
car sees a call before it rings. Also adds pinnable nav bar shortcuts,
lowers minSdk to 31 for wider device support, and bumps to 0.0.04-pre.

.gitignore

@@ -22,4 +22,5 @@ keystore.properties
 /docs/cert-sweep.sh
 archive/
 CLAUDE.md
-*.pdf
+*.pdf
+extraction/