chore(audience-sample-app): wire up package, asmdef, README

Unity-package wiring for the sample under examples/audience:
* Packages/manifest.json points at com.immutable.audience locally
* Scripts/Immutable.Audience.Samples.SampleApp.asmdef declares the
  sample assembly + dependencies
* Top-level README

Removes Assets/Scenes.meta (legacy folder meta — sample's scene now
lives at Assets/SampleApp/Scenes/).

Author: ImmutableJeffrey

examples/audience/Assets/SampleApp/README.md

@@ -0,0 +1,9 @@
+# Immutable Audience — Sample App
+
+A demo of the `ImmutableAudience` SDK that exercises every public API.
+
+## How to use
+
+1. Open `Scenes/SampleApp.unity` and press Play.
+2. Paste your publishable key and initialise the SDK.
+3. Use the controls to exercise the SDK; the log pane records every call and response.

examples/audience/Assets/SampleApp/README.md.meta

@@ -0,0 +1,14 @@
+{
+    "name": "Immutable.Audience.Samples.SampleApp",
+    "rootNamespace": "Immutable.Audience.Samples.SampleApp",
+    "references": ["Immutable.Audience.Runtime"],
+    "includePlatforms": [],
+    "excludePlatforms": [],
+    "allowUnsafeCode": false,
+    "overrideReferences": false,
+    "precompiledReferences": [],
+    "autoReferenced": false,
+    "defineConstraints": [],
+    "versionDefines": [],
+    "noEngineReferences": false
+}

examples/audience/Assets/Scenes.meta …s/audience/Assets/SampleApp/Scripts.metaexamples/audience/Assets/Scenes.meta renamed to examples/audience/Assets/SampleApp/Scripts.meta examples/audience/Assets/Scenes.meta renamed to examples/audience/Assets/SampleApp/Scripts.meta

@@ -1,5 +1,6 @@
 {
   "dependencies": {
+    "com.immutable.audience": "file:../../../src/Packages/Audience",
     "com.unity.collab-proxy": "2.5.2",
     "com.unity.feature.development": "1.0.1",
     "com.unity.ide.rider": "3.0.31",

examples/audience/Assets/SampleApp/Scripts/Immutable.Audience.Samples.SampleApp.asmdef

@@ -1,5 +1,11 @@
 {
   "dependencies": {
+    "com.immutable.audience": {
+      "version": "file:../../../src/Packages/Audience",
+      "depth": 0,
+      "source": "local",
+      "dependencies": {}
+    },
     "com.unity.collab-proxy": {
       "version": "2.5.2",
       "depth": 0,