Add glossary for improved user understanding

[ChinonyeRuth]

This pull request proposes adding a glossary section to the Klaytn documentation. This glossary will define key terms encountered throughout the documentation, particularly those related to blockchain technology.

Proposed changes

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• Minor Issues and Typos
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• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

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[github-actions]

CLA Assistant Lite bot:
Thank you for your submission, we really appreciate it. Like many open-source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution. You can sign the CLA by just posting a Pull Request Comment same as the below format.

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[CLAassistant]

All committers have signed the CLA.

[scott-klaytn]

@ChinonyeRuth Thank you for contribution to Klaytn docs. Two things I'd like to comment:

1. Please post "I have read the CLA Document and I hereby sign the CLA" in a comment in this PR.
2. FYI, we have an existing Glossary page under the Learn section. Please move these entries to the page. If you want them to be more contextual, please use the tooltip functionality. If you have any questions, feel free to ping me.

[scott-klaytn]

Thank you for your contribution! Due to repository migration, we're closing this PR for now. We plan to reopen contributions in the new Kaia docs repo once it's public. We encourage you to resubmit your PR there then.