fix: correct Trusted Agent Provider delegation SVG diagram

[AdijeShen]

Summary

The mandate_delegation_trusted_agent_provider.svg was incorrectly duplicated from mandate_delegation_user_credential.svg, showing the User Credential model instead of the Trusted Agent Provider model.

Problem

Both SVGs had identical content with:

• 4 participants: User, Trusted Surface, Agent, Issuer
• "Issue User Credential (In Advance)" pre-issuance step
• "issuer_signed(Credential) w/user Pk" and "Issuer_signed(UserCredential) + user_signed(Mandate)" messages

This does not match the Trusted Agent Provider model described in docs/ap2/agent_authorization.md, which states:

"This model does not require a pre-issued credential."
"The Agent Provider uses a securely stored signing key to create the Mandate."

Fix

Replaced the diagram with the correct Trusted Agent Provider flow:

Aspect	Before (incorrect, same as UC)	After (correct, matches spec)
Participants	User, Trusted Surface, Agent, Issuer	User, Agent Provider Trusted Surface, Agent
Pre-issuance	"Issue User Credential (In Advance)"	Removed (not needed)
Request	Authorization Request(Mandate Content)	Authorization Request(Mandate Content, agent_pk)
Signing	issuer_signed(Credential) w/user Pk	Sign Mandate w/ Agent Provider key
Response	Issuer_signed(UserCredential) + user_signed(Mandate)	Signed Mandate

Test plan

• Visually verify the new SVG renders correctly in the docs
• Confirm the diagram matches the Trusted Agent Provider description in agent_authorization.md
• Confirm mandate_delegation_user_credential.svg is unchanged

🤖 Generated with Claude Code

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[gemini-code-assist]

Code Review

This pull request updates the mandate_delegation_trusted_agent_provider.svg diagram to reflect a revised delegation flow involving an Agent Provider and Trusted Surface. The review feedback identifies a technical error in the SVG path data where an incorrect Bézier control point causes a message arrow to point in the wrong direction. Additionally, it is recommended to add a viewBox attribute to the SVG root element to ensure the diagram scales correctly across different screen sizes.

[gemini-code-assist]

The path for the "Signed Mandate" response has an incorrect control point for the cubic Bézier curve. The message flows from the Agent Provider (x=235) to the Agent (x=530), so the arrow should point right. However, the current control point 535 (which is End + 5) results in a left-pointing tangent at the end point 530. It should be 525 (which is End - 5) to ensure the arrow points in the correct direction.

<text x="382.5" y="346.5" text-anchor="middle" font-family="Roboto" font-size="16px" stroke="none" fill="#000000" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0); text-anchor: middle; font-family: Roboto; font-size: 16px;"><tspan dy="5.5" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Signed Mandate</tspan></text><path fill="none" stroke="#000000" d="M235,356C235,356,525,356,530,356" stroke-width="2" marker-end="url(#raphael-marker-endblock55-obj5)" stroke-dasharray="6,3" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0);"></path>

[gemini-code-assist]

It is recommended to include a viewBox attribute in the <svg> tag. This ensures the diagram scales correctly and maintains its aspect ratio across different screen sizes and resolutions.

<svg xmlns="http://www.w3.org/2000/svg" width="620" height="480" viewBox="0 0 620 480" xmlns:xlink="http://www.w3.org/1999/xlink">