Xcode – Flutter error: "CocoaPods not installed or not in valid state."

Could the problem be that Android Studio can’t find the path to CocoaPods?

I’m trying to test my app on my iPhone from Android Studio. The error I get is

Warning: CocoaPods not installed. Skipping pod install.
  CocoaPods is used to retrieve the iOS and macOS platform side's plugin code that responds to your plugin usage on the Dart side.
  Without CocoaPods, plugins will not work on iOS or macOS.
  For more info, see https://flutter.dev/platform-plugins
To install see https://guides.cocoapods.org/using/getting-started.html#installation for instructions.

Exception: CocoaPods not installed or not in valid state.

I ran gem list and the list of installed gems include:

gem list
 
cocoapods (1.11.2)
cocoapods-core (1.11.2)
cocoapods-deintegrate (1.0.5)
cocoapods-downloader (1.5.1)
cocoapods-plugins (1.0.0)
cocoapods-search (1.0.1)
cocoapods-trunk (1.6.0)
cocoapods-try (1.2.0)

I ran

sudo gem uninstall cocoapods && sudo gem install cocoapods

I ran

flutter clean

I restarted Android Studio.

I ran File > Invalidate Caches… > Invalidate and Restart.

I ran

cd ios
pod install

This threw this error:

[!] CocoaPods did not set the base configuration of your project because your project already has a custom config set. In order for CocoaPods integration to work at all, please either set the base configurations of the target `Runner` to `Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig` or include the `Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig` in your build configuration (`Flutter/Release.xcconfig`).

The Stack Overflow answers about that error message say to fix the issue in Xcode. But when I try to open my Android Studio project in Xcode I get this error:

Could not open file. (/Users/TDK/StudioProjects/Kabbalah)

Here’s an odd thing. When I uninstall cocoapods they don’t go away:

sudo gem uninstall cocoapods
Remove executables:
        pod, sandbox-pod

in addition to the gem? [Yn]  
Removing pod
Removing sandbox-pod
Successfully uninstalled cocoapods-1.11.2
➜  Kabbalah git:(main) ✗ gem list

*** LOCAL GEMS ***

abbrev (default: 0.1.0)
activesupport (6.1.4.4)
addressable (2.8.0)
algoliasearch (1.27.5)
atomos (0.1.3)
base64 (default: 0.1.0)
benchmark (default: 0.1.1)
bigdecimal (default: 3.0.0)
bundler (default: 2.2.32)
bundler-unload (1.0.2)
CFPropertyList (3.0.5)
cgi (default: 0.2.1)
claide (1.1.0, 1.0.3)
cocoapods (1.11.2)
cocoapods-core (1.11.2)
cocoapods-deintegrate (1.0.5)
cocoapods-downloader (1.5.1)
cocoapods-plugins (1.0.0)
cocoapods-search (1.0.1)
cocoapods-trunk (1.6.0)
cocoapods-try (1.2.0)

What do I do next? In case this wasn’t obvious, I don’t know how to use Xcode.