Add visuals for proving + privacy workflows (Docs)

Feedback:
Logic and account structure felt intuitive, but the proving workflow and privacy flow were harder to follow. More diagrams/visuals would make it much clearer.

Ask:
Add diagrams or step-by-step visuals to docs that explain:

- How the proving workflow fits together
- How the privacy flow works in practice

Why:
Makes the workflows easier to grasp, especially for new devs.

**This feedback came through DevRel applications.**

Review the existing documentation in the repository to understand the current explanations of the proving workflow and privacy flow. Identify sections that would benefit from diagrams. Create simple visuals (e.g., using Mermaid, draw.io, or similar tools) illustrating the step-by-step processes. Integrate these diagrams into the relevant markdown files, ensuring they clarify the logical flow for new developers.

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