Rewrite phase & sprint plan with new priority ordering

Reorganized roadmap based on owner priorities:
1. Foundry Completion (F-4.5, F-QoL, F-5)
2. System Modularity & Owner Experience (new Phase X: X-1 through X-5)
3. Maps & Spatial (W-2, W-2.5)
4. Collaboration & Polish (U-series, W-1, W-4)
5. Content & Integrations (T-3/4, W-3/5/6)
6. Foundry Advanced (F-6, F-7)

New sprints added: F-QoL (sync diagnostics), X-1 (upload wizard),
X-2 (auto entity presets), X-3 (system widgets), X-4 (system diagnostics),
X-5 (character sheet layout blocks).

https://claude.ai/code/session_01PeB1HsjEYNPSY2iqa7sqqR

Author: claude