Arch: Finalize V3 Auth modularization and Unified Agent spec.

- Integrated zero-dependency Auth models and dependencies_v3.py.
- Successfully resolved circular dependency boot loops.
- Verified site_domain search exception via verify_v3_exceptions.py.
- Refined Unified Agent Architecture with Storage Layer and API-driven access details.
- Updated project roadmap and milestones in GEMINI.md.

documentation/UNIFIED_AGENT_ARCH.md

@@ -48,6 +48,7 @@ The **Unified Aether AI Agent** is a single, cohesive AI entity designed to elim
 ### F. Storage Layer (Syncthing / Hosted Files)
 *   **Location:** `/home/scott/OSIT/hosted_files/` (Main Workstation) and synchronized Remote Servers.
 *   **Role:** Extremely important persistent storage for files served via the API (e.g., `hosted_file`, `event_file`).
+*   **API-Driven Access:** Files are frequently accessed/downloaded directly via API endpoints. The agent must understand the routing and security logic (JWT validation) governing these downloads.
 *   **Synchronization:** Managed via **Syncthing** (similar to the `agents_sync` directory), ensuring real-time mirroring across the Aether ecosystem.
 *   **Agent Access Requirements:**
     *   Full filesystem access to the local hosted files directory.