feat: Android companion app improvements & gateway URL camera payloads (#13541)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: 9c179c9c3192ec76059f5caac1e8de8bdfb257ce
Co-authored-by: smartprogrammer93 <33181301+smartprogrammer93@users.noreply.github.com>
Co-authored-by: steipete <58493+steipete@users.noreply.github.com>
Reviewed-by: @steipete

apps/android/app/proguard-rules.pro

@@ -0,0 +1,28 @@
+# ── App classes ───────────────────────────────────────────────────
+-keep class ai.openclaw.android.** { *; }
+
+# ── Bouncy Castle ─────────────────────────────────────────────────
+-keep class org.bouncycastle.** { *; }
+-dontwarn org.bouncycastle.**
+
+# ── CameraX ───────────────────────────────────────────────────────
+-keep class androidx.camera.** { *; }
+
+# ── kotlinx.serialization ────────────────────────────────────────
+-keep class kotlinx.serialization.** { *; }
+-keepclassmembers class * {
+    @kotlinx.serialization.Serializable *;
+}
+-keepattributes *Annotation*, InnerClasses
+
+# ── OkHttp ────────────────────────────────────────────────────────
+-dontwarn okhttp3.**
+-dontwarn okio.**
+-keep class okhttp3.internal.platform.** { *; }
+
+# ── Misc suppressions ────────────────────────────────────────────
+-dontwarn com.sun.jna.**
+-dontwarn javax.naming.**
+-dontwarn lombok.Generated
+-dontwarn org.slf4j.impl.StaticLoggerBinder
+-dontwarn sun.net.spi.nameservice.NameServiceDescriptor