Fix nix-shell dev container build errors
Onboarding — add tracker type choice as first step
Price tracking — verify and wire up end-to-end
Make price tracking optional and off by default
Onboarding — add tracker type choice as first step
Frontend — multi-tracker UI, generalize financial copy
Onboarding — two-path flow (asset vs non-asset)
Backend — Tracker model, refactor Purchase → Entry
Schema refactor — introduce Tracker, rename purchases to entries
Fix nix-shell dev container build errors
Generalize copy — remove VWCE mentions