issue 887: fixed auto reloading and enable background reloading

[Vansh5632]

What's this PR do?
Fixes #877
Introduces a ReconnectUtil class to manage internet connection interruptions in WebView, with a Fibonacci backoff strategy for reconnection attempts and graceful error handling.

Any background context you want to provide?
The utility provides a robust mechanism for handling temporary network disconnections, with:

• Fibonacci backoff to prevent overwhelming network resources
• Background webview reloading
• Detailed logging
• User-friendly offline error messaging

You have tested this PR on:

• Windows
• Linux/Ubuntu
• macOS

[timabbott]

Please self-review and clean up your PR; .vagrant should not be present :).

[zulipbot]

Hello @Vansh5632, it seems like you have referenced #877 in your pull request description, but you have not referenced them in your commit message description(s). Referencing an issue in a commit message automatically closes the corresponding issue when the commit is merged, which makes the issue tracker easier to manage.

Please run git commit --amend in your command line client to amend your commit message description with Fixes #877..

An example of a correctly-formatted commit:

commit fabd5e450374c8dde65ec35f02140383940fe146
Author: zulipbot
Date:   Sat Mar 18 13:42:40 2017 -0700

    pull requests: Check PR commits reference when issue is referenced.

    Fixes #51.

To learn how to write a great commit message, please refer to our guide.

[whilstsomebody]

Hi @Vansh5632 , please read the contribution guide before moving ahead. Before any further review, you have to correct your PR:

• Clean the commit history.
• Provide some screenshots of you changes.