Update the Android development enviornment setup

1. Update `ANDROID_SDK_ROOT` to `ANDROID_HOME`. The former variable is
   deprecated. (see https://developer.android.com/tools/variables#envar)
2. Remove `ANDROID_NDK_HOME` environment variable. This should allow the
   build script to work out of the box for more folks.
3. Check that Java is on the `PATH` as opposed to just installing it.
   `asdf` and other runtime management tools are pretty popular, and all
   we care about is that the Java version is accessible.
4. Remove calls to `sudo`. Check to see if CocoaPods exists, if it
   doesn't install it using Homebrew which doesn't require `sudo`.

veilid-flutter/setup_flutter.sh

@@ -59,26 +59,13 @@ if [ "$OS" == "linux" ]; then
     flutter config --enable-linux-desktop --enable-android
 
 elif [ "$OS" == "macos" ]; then
-
-    # # ensure x86_64 homebrew is installed
-    # if [ -f /usr/local/bin/brew ] &> /dev/null; then 
-    #     echo '[X] x86_64 homebrew is available'
-    # else
-    #     echo 'x86_64 homebrew is not available, run this:'
-    #     echo 'arch -x86_64 zsh'
-    #     echo '/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"'
-    #     exit 1
-    # fi
-
-    # ensure packages are installed
-    # if [ "$BREW_USER" == "" ]; then
-    #     BREW_USER=`ls -lad /usr/local/bin/. | cut -d\  -f4`
-    #     echo "Must sudo to homebrew user \"$BREW_USER\" to install LLVM package:"
-    # fi
-    # sudo -H -u $BREW_USER arch -x86_64 /usr/local/bin/brew install llvm
-    echo "Must sudo to root to install CocoaPods gem:"
-    # sudo arch -x86_64 gem install ffi
-    sudo arch -x86_64 gem install cocoapods
+    # check if cocoapods is installed, if its not, install it
+    if command -v pod &> /dev/null; then
+        echo '[X] CocoaPods is available in the path'
+    else
+        echo 'CocoaPods is not available in the path, installing it now'
+        brew install cocoapods
+    fi
 
     if [ "$(uname -p)" == "arm" ]; then
         sudo softwareupdate --install-rosetta --agree-to-license