fix: cap camera snap payload size

apps/android/app/src/test/java/com/steipete/clawdis/node/node/JpegSizeLimiterTest.kt

@@ -0,0 +1,47 @@
+package com.steipete.clawdis.node.node
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import kotlin.math.min
+
+class JpegSizeLimiterTest {
+  @Test
+  fun compressesLargePayloadsUnderLimit() {
+    val maxBytes = 5 * 1024 * 1024
+    val result =
+      JpegSizeLimiter.compressToLimit(
+        initialWidth = 4000,
+        initialHeight = 3000,
+        startQuality = 95,
+        maxBytes = maxBytes,
+        encode = { width, height, quality ->
+          val estimated = (width.toLong() * height.toLong() * quality.toLong()) / 100
+          val size = min(maxBytes.toLong() * 2, estimated).toInt()
+          ByteArray(size)
+        },
+      )
+
+    assertTrue(result.bytes.size <= maxBytes)
+    assertTrue(result.width <= 4000)
+    assertTrue(result.height <= 3000)
+    assertTrue(result.quality <= 95)
+  }
+
+  @Test
+  fun keepsSmallPayloadsAsIs() {
+    val maxBytes = 5 * 1024 * 1024
+    val result =
+      JpegSizeLimiter.compressToLimit(
+        initialWidth = 800,
+        initialHeight = 600,
+        startQuality = 90,
+        maxBytes = maxBytes,
+        encode = { _, _, _ -> ByteArray(120_000) },
+      )
+
+    assertEquals(800, result.width)
+    assertEquals(600, result.height)
+    assertEquals(90, result.quality)
+  }
+}