refactor: rename apps/ to clients/ + update architecture docs

Rename apps/ → clients/ for clarity:
- app/ (singular) = Python backend (FastAPI, server-rendered web UI)
- clients/ (plural) = standalone client applications (API consumers)

The web storefront/store/admin stays in app/ because it's server-
rendered Jinja2, not a standalone frontend. clients/ is for native
apps that connect to the API externally.

Updated:
- docs/architecture/overview.md — added clients/ to project structure
- clients/terminal-android/SETUP.md — updated path references

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

clients/terminal-android/app/src/main/AndroidManifest.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <!-- Network access for API calls -->
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+
+    <!-- Camera for QR/barcode scanning -->
+    <uses-permission android:name="android.permission.CAMERA" />
+    <uses-feature android:name="android.hardware.camera" android:required="false" />
+
+    <application
+        android:name=".RewardFlowApp"
+        android:allowBackup="false"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.RewardFlowTerminal"
+        tools:targetApi="35">
+
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:screenOrientation="landscape"
+            android:configChanges="orientation|screenSize|screenLayout|keyboardHidden"
+            android:windowSoftInputMode="adjustResize"
+            android:lockTaskMode="if_whitelisted">
+
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+                <category android:name="android.intent.category.HOME" />
+                <category android:name="android.intent.category.DEFAULT" />
+            </intent-filter>
+        </activity>
+    </application>
+</manifest>