[WIP] Update architecture document for production readiness

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Architecture Document</issue_title>
<issue_description>## Description
Deep technical documentation.

Tasks

• System overview diagram
• Component responsibilities
• Data flow diagrams
• Request lifecycle
• Database schema documentation
• Storage layout documentation</issue_description>

<agent_instructions>make it prod ready, also resolve all conflict</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Architecture Document #65

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