Correctly using NSAppleScript for Mail.app plugin

Context

• I'm working on a Mail.app plugin. I would like to disseminate plugin via AppStore.
• I'm interested in exposing a functionality to user enabling user to choose if plugin should apply to all or selected email account.
• My intention is to use AppleScript to get a list of available email accounts and expose the list to the end-user via SwiftUI

Sourcing account information

Apple Script

I'm using the following AppleScript

tell application "Mail"
    set accountDict to {}
    repeat with acc in accounts
        set accName to name of acc
        set accEmails to email addresses of acc
        set accountDict's end to {accName:accEmails}
     end repeat
     return accountDict
 end tell

The above generates expected results when executed using Script Editor.

Swift Implementation

This is still incomplete but shows the overall plan.

//
//  EmailAccounts.swift
import Foundation

enum EmailScriptError: Error {
    case scriptExecutionError(String)
}

struct EmailAccounts {
    func getAccountNames() -> [String]? {
        let appleScriptSource = """
        tell application "Mail"
            set accountDict to {}
            repeat with acc in accounts
                set accName to name of acc
                set accEmails to email addresses of acc
                set accountDict's end to {accName:accEmails}
            end repeat
            return accountDict
        end tell
        """

        var error: NSDictionary?
        var accountNames: [String] = []

        // Create script object, exit if fails
        guard let scriptObject = NSAppleScript(source: appleScriptSource) else {
            return nil
        }

        // Execute script and store results, nil on error
        let scriptResult = scriptObject.executeAndReturnError(&error)
        if error != nil { return nil }

        // Iterate over results
        for index in 0...scriptResult.numberOfItems {
            if let resultEntry = scriptResult.atIndex(index) {
                if let resultString = resultEntry.stringValue {
                   // Process result handling
                   // accountNames.append(resultString)
                }
            }

        }

        return accountNames

    }
}

Questions

1. Most important one, can I deploy the App on the App Store and use NSAppleScript as shown above?
2. If yes can I use the script in the manner shown above or will I need to store the script in User > Library > Application Scripts location and source it from there. This is outlined in the Scripting from a Sandbox article by Craig Hockenberry, which I cannot link due to being hosted within a not-permitted domain.
3. If yes what entitlements I need to give to the target.
4. I understand that I wouldn't be able to use ScriptingBridge, which feels more robust but wouldn't permit me to deploy the app on the AppStore.
5. My key objective is to programatically identify mail accounts available to Mail.app, if there is a wiser / easier way of doing that I would be more than receptive.