Use linked list to manage key-repeat events

[PMohanJ]

Reference the issue numbers and reviewers Use # and @ to tag issues and reviewers. @ehfd

Explain relevant issues and how this pull request solves them Replacing queue data structure with linked list to facilitate dynamic insertions and removal of key-repeat event data.

Describe the changes in code and its dependencies and justify that they work as intended after testing The changes include the implementation of linked list data structures on both client and server and replacing the queue data structure with linked-list in the code part where key-events are handled.

Describe alternatives you've considered NA

Additional context NA

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