App 2.22.1: gear badge shows only P; Logs list the raw gear codes

The badge said "D" for every gear that was not P, so N and R read as D.
EVHardware now passes on the raw gear code; the badge shows P for 1,
no letter for codes not yet mapped, "—" when unread. The Logs tab lists
each change of the code with time and speed, to match R, N and D on
the car. Emulator only.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LhzAVaUyqcw5PkGjz4mWW6

app/src/test/java/com/evsuite/abrp/GearTest.java

@@ -0,0 +1,22 @@
+package com.evsuite.abrp;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+/** The gear letter — pure JVM. */
+public class GearTest {
+
+    @Test
+    public void onlyParkIsNamed() {
+        assertEquals("P", Gear.label(1));
+        assertEquals("", Gear.label(2));
+        assertEquals("", Gear.label(3));
+        assertEquals("", Gear.label(4));
+    }
+
+    @Test
+    public void unreadIsADash() {
+        assertEquals("—", Gear.label(null));
+    }
+}