Add full sprint pricing workflow and supporting infrastructure:
- New sidebar navigation entry for the sprint dashboard
- PocketBase category collection schema and migration script
- Server API routes for sprint item claims, attachments, counts, and file proxying
- Dev identity utilities and UI switcher for multi-user testing
- Reusable FilterTabs component replacing ItemStatusTabs
- Updated TypeScript types for sprint-related entities
Also include:
- Fix PocketBase file URL method casing (getUrl → getURL) across codebase
- Add development utility, smoke test, and helper scripts
- Update package.json with new sprint migration command
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