Resolve "Add Agent/Flow specific SVGs"

Purpose

Screenshots

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Checklist

For a new icon and/or illustration:

• Link to related design issue: #449 (closed)
• If this adds an icon ensure that it follows the new icon checklists.
• If this adds an illustration ensure that it follows the new illustration checklists.

For third-party trademarks:

• If this adds or updates an icon or illustration that includes a third-party trademark, ensure that it follows the process for adding third-party trademarks to GitLab.

Closes #449 (closed)