wifi: package hostapd and wpa_supplicant into apex

* This is now possible on Android 15 QPR2. Use cuttlefish as reference.
  https://android.googlesource.com/device/google/cuttlefish/+/refs/tags/android-15.0.0_r20/apex/com.google.cf.wpa_supplicant/
* Create local copies of the service entries. Generally creating the
  directories for wireless subsystem happens on trigger 'on post-fs-data'.
  Since apexd for non-bootstrap APEXs starts 'on post-fs-data', this
  trigger is not available for vendor APEX packages. Use trigger
  'apex.all.ready=true' instead which is later still within post-fs-data.
  https://source.android.com/docs/core/ota/vendor-apex#init-scripts
* Create a local copy of wpa_supplicant_overlay.conf. It hasn't been updated
  in ten years in hardware/broadcom/wlan. TODO: Check relevance.

wifi/Android.bp

@@ -0,0 +1,68 @@
+// Copyright (C) 2025 KonstaKANG
+//
+// SPDX-License-Identifier: Apache-2.0
+
+prebuilt_etc {
+    name: "android.hardware.wifi.hostapd-service.rc",
+    src: "android.hardware.wifi.hostapd-service.rc",
+    installable: false,
+}
+
+prebuilt_etc {
+    name: "android.hardware.wifi.supplicant-service.rc",
+    src: "android.hardware.wifi.supplicant-service.rc",
+    installable: false,
+}
+
+prebuilt_etc {
+    name: "wpa_supplicant.conf.rpi",
+    src: ":wpa_supplicant_template.conf",
+    filename: "wpa_supplicant.conf",
+    relative_install_path: "wifi",
+    installable: false,
+}
+
+prebuilt_etc {
+    name: "wpa_supplicant_overlay.conf",
+    src: "wpa_supplicant_overlay.conf",
+    relative_install_path: "wifi",
+    installable: false,
+}
+
+apex {
+    name: "com.android.hardware.wifi.hostapd.rpi4",
+    manifest: "apex_manifest_hostapd.json",
+    file_contexts: "apex_file_contexts_hostapd",
+    key: "com.android.hardware.key",
+    certificate: ":com.android.hardware.certificate",
+    updatable: false,
+    vendor: true,
+
+    binaries: [
+        "//external/wpa_supplicant_8/wpa_supplicant/wpa_supplicant:hostapd",
+    ],
+    prebuilts: [
+        "android.hardware.wifi.hostapd-service.rc",
+        "android.hardware.wifi.hostapd.xml.prebuilt",
+    ],
+}
+
+apex {
+    name: "com.android.hardware.wifi.supplicant.rpi4",
+    manifest: "apex_manifest_supplicant.json",
+    file_contexts: "apex_file_contexts_supplicant",
+    key: "com.android.hardware.key",
+    certificate: ":com.android.hardware.certificate",
+    updatable: false,
+    vendor: true,
+
+    binaries: [
+        "//external/wpa_supplicant_8/wpa_supplicant/wpa_supplicant:wpa_supplicant",
+    ],
+    prebuilts: [
+        "android.hardware.wifi.supplicant-service.rc",
+        "android.hardware.wifi.supplicant.xml.prebuilt",
+        "wpa_supplicant.conf.rpi",
+        "wpa_supplicant_overlay.conf",
+    ],
+}

wifi/android.hardware.wifi.hostapd-service.rc

@@ -0,0 +1,13 @@
+on property:apex.all.ready=true
+    mkdir /data/vendor/wifi 0770 wifi wifi
+    mkdir /data/vendor/wifi/hostapd 0770 wifi wifi
+    mkdir /data/vendor/wifi/hostapd/sockets 0770 wifi wifi
+
+service hostapd /apex/com.android.hardware.wifi.hostapd.rpi4/bin/hw/hostapd
+    interface aidl android.hardware.wifi.hostapd.IHostapd/default
+    class main
+    capabilities NET_ADMIN NET_RAW
+    user wifi
+    group wifi net_raw net_admin
+    disabled
+    oneshot

wifi/android.hardware.wifi.supplicant-service.rc

@@ -0,0 +1,18 @@
+on property:apex.all.ready=true
+    mkdir /data/vendor/wifi 0770 wifi wifi
+    mkdir /data/vendor/wifi/wpa 0770 wifi wifi
+    mkdir /data/vendor/wifi/wpa/sockets 0770 wifi wifi
+
+service wpa_supplicant /apex/com.android.hardware.wifi.supplicant.rpi4/bin/hw/wpa_supplicant \
+    -O/data/vendor/wifi/wpa/sockets -dd \
+    -g@android:wpa_wlan0
+    #   we will start as root and wpa_supplicant will switch to user wifi
+    #   after setting up the capabilities required for WEXT
+    #   user wifi
+    #   group wifi inet keystore
+    interface aidl android.hardware.wifi.supplicant.ISupplicant/default
+    class main
+    socket wpa_wlan0 dgram 660 wifi wifi
+    user root
+    disabled
+    oneshot

wifi/apex_file_contexts_hostapd

@@ -0,0 +1,3 @@
+(/.*)?                    u:object_r:vendor_file:s0
+/etc(/.*)?                u:object_r:vendor_configs_file:s0
+/bin/hw/hostapd           u:object_r:hal_wifi_hostapd_default_exec:s0

wifi/apex_file_contexts_supplicant

@@ -0,0 +1,3 @@
+(/.*)?                    u:object_r:vendor_file:s0
+/etc(/.*)?                u:object_r:vendor_configs_file:s0
+/bin/hw/wpa_supplicant    u:object_r:hal_wifi_supplicant_default_exec:s0

wifi/apex_manifest_hostapd.json

@@ -0,0 +1,4 @@
+{
+  "name": "com.android.hardware.wifi.hostapd.rpi4",
+  "version": 1
+}

wifi/apex_manifest_supplicant.json

@@ -0,0 +1,4 @@
+{
+  "name": "com.android.hardware.wifi.supplicant.rpi4",
+  "version": 1
+}

wifi/wpa_supplicant_overlay.conf

@@ -0,0 +1,5 @@
+disable_scan_offload=1
+wowlan_triggers=any
+p2p_disabled=1
+filter_rssi=-75
+no_ctrl_interface=