Design portal cash tracing dashboard and interactive mockup

Explore admin cash investigation UX in an isolated feature worktree. Build a standalone HTML prototype using synthetic data, informed by existing portal trade audit and persistence patterns. Cover cash sources/sinks, balance reconciliation, character/account investigation and multi-hop transfers with explicit uncertainty for fungible money. Identify candidate ledger models and ingestion gaps; do not implement production migrations or endpoints yet. Acceptance: usable mockup with working investigation controls, clearly labelled synthetic data and coverage limitations; browser validation; concise proposed data model and next implementation decisions. Delivered in /home/mathias/Projects/worktrees/engines-cash-tracing on feature/admin-cash-tracing, under PRK.PlayerPortal/prototypes/cash-tracing. README captures candidate balanced journal/entry, wallet, checkpoint and coverage models, integration constraints and unresolved supply scope. Four Node tests pass, including filtered export Blob payload; Chrome verified investigation flows and desktop/mobile layouts. Default trace's six events are correct because the return route reaches the final sink within three hops. Browser download contents were not inspectable; no production engine/database integration was implemented or tested. Changes committed on feature/admin-cash-tracing; current data-model direction is the simpler best-effort cash-history service rather than the earlier balanced-entry proposal. Research follow-up: README records primary-source EVE/Guild Wars 2/OSRS reporting and PlayFab transaction API findings with links, limitations and PRK priorities. Removed slogans, repeated explanatory copy and implementation notes from the UI. GM labels are Cash history, Balance check and Follow money, retaining Faucets/Sinks per user vocabulary. Added reason-level event/account counts, account details and elapsed payment times, and a dynamic starting-payment panel. Five Node tests pass including wording and filtered export payload. Follow-up Chrome runs were cancelled; the latest revision has automated validation only, not a completed new browser pass. Pull request: #2798 — https://git.project-rk.com/prk/engines/pulls/2798 (draft/WIP), feature/admin-cash-tracing → develop. Includes prototype commit 48d118608 and the cash-history foundation.