[Bug]: The function snippet generated for an isolated variable in a library function is incorrect

[nipunayf]

Description

The function snippet generated for a library function under an isolated variable does not contain the isolated keyword, and hence, the CA produces erroneous code. Please refer to the following:

https://github.com/ballerina-platform/ballerina-lang/assets/59343084/b62570b8-f673-49d9-8968-eae1fd55e151

Steps to Reproduce

Prompt for completions for the following cursor position.

import ballerina/http;

service / on new http:Listener(9090) {
    private int[] items = [];

    isolated resource function name .() {
        self.items.forEach(fu<CURSOR>);
    }
}

Affected Version(s)

Ballerina 2201.8.6 (Swan Lake Update 8)

OS, DB, other environment details and versions

OS: macOS 14.2.1 23C71 JDK: openjdk 17.0.8 2023-07-18

Related area

-> Compilation

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