Overhaul the VR menu UI: header, tabs, live video options, hover/click feedback, i18n, and dragging

- Header with title, git-tag-derived version, and a live FPS/frame-time/
  CPU/GPU-utilization/free-memory stats ribbon below the tab bar (FPS via
  a new per-frame tracker in xr_session.c; CPU/GPU via the OpenXR
  XR_META_performance_metrics extension, gracefully unavailable on
  runtimes that don't support it)
- Bottom tab bar with a live-editable Video Options tab (renderer/
  resolution), applying changes immediately via qs_config.c
- Hover and press feedback on every menu/keyboard button via a
  StateListDrawable (Android's default ripple never animates on this
  permanently unattached view tree), with a lighter default button color
  for visibility
- i18n for all menu/keyboard chrome text, following the game's own
  language setting (Strings.java)
- The main menu is now draggable via its header, matching the keyboard;
  xr_input.c's drag handling is generalized to per-overlay state instead
  of being keyboard-only
- The keyboard's title bar now matches the menu header's style

android/app/build.gradle

@@ -29,9 +29,33 @@ if (prebuiltDir == null) {
 }
 
 // Set by build-apk.sh (see build-image/version.sh, shared with the
-// desktop tarball's versioning) via -PquestshockVersionName/Code. Default
-// here only covers a direct, unsupported `gradlew` invocation.
-def questshockVersionName = project.hasProperty('questshockVersionName') ? project.property('questshockVersionName') : '0.0.0-dev'
+// desktop tarball's versioning) via -PquestshockVersionName/Code. Building
+// directly from Android Studio (the normal day-to-day workflow - see
+// README) never passes that property, so the default below has to carry
+// its own weight rather than just being a fallback for some rare, other,
+// unsupported path: it runs `git describe` itself, the same way
+// engine/CMakeLists.txt's own PROJECT_REVERSION_STRING does for the
+// engine's *own* separate version string - "vX.Y.Z" on a clean tagged
+// commit, or "vX.Y.Z-N-gHASH[-dirty]" otherwise, so a build between
+// releases is still identifiable from the in-headset menu (see
+// MenuOverlay.java's header, which reads BuildConfig.VERSION_NAME).
+def gitDescribeVersionName = {
+    try {
+        def proc = ["git", "-C", projectDir.toString(), "describe", "--tags", "--always", "--dirty"].execute()
+        proc.waitFor()
+        if (proc.exitValue() == 0) {
+            def out = proc.text.trim()
+            if (out) {
+                return out
+            }
+        }
+    } catch (Exception ignored) {
+        // git not on PATH, or this isn't a git checkout at all (e.g. a
+        // source tarball) - fall through to the placeholder below.
+    }
+    return "0.0.0-dev"
+}
+def questshockVersionName = project.hasProperty('questshockVersionName') ? project.property('questshockVersionName') : gitDescribeVersionName()
 def questshockVersionCode = project.hasProperty('questshockVersionCode') ? project.property('questshockVersionCode').toInteger() : 1
 
 // Auto-refreshes the staged, patched engine/ and gl4es-src/ copies and
@@ -189,6 +213,13 @@ android {
         }
     }
 
+    // Generates BuildConfig (specifically BuildConfig.VERSION_NAME, read by
+    // MenuOverlay.java's header) - off by default since AGP 8.0, so this
+    // has to be requested explicitly.
+    buildFeatures {
+        buildConfig true
+    }
+
     lint {
         abortOnError false
     }