- Replace grouped cashflow BarChart with ComposedChart: expense categories
as colour-coded stacked bars + amber savings-rate % line on right Y-axis
- Add category colour legend below chart (matches stacked bars)
- Horizontal category bar chart now uses per-category colours
- Breakdown table: click any category row to expand/collapse individual
transactions; each transaction has an inline category dropdown that
calls PATCH /api/transactions/:id → transaction_overrides, then
invalidates analytics query so totals update immediately
Add rules engine with CRUD API, condition/action evaluation, and apply-all endpoint.
UI: rule builder form with field/operator/value conditions, tag multi-select, apply button with result stats.
- tags table: name, color; transaction_tags junction table
- GET/POST /api/tags; DELETE /api/tags/:id
- POST/DELETE /api/transactions/:id/tags for per-transaction tagging
- Bulk tag/untag via /api/transactions/bulk (action: tag/untag)
- Tags returned inline with transaction list via LATERAL join
- Tag filter on Transactions page
- Bulk "Tag as..." in bulk action bar
- Tag pills + "+" picker on each transaction row
- /tags page: create with color picker, list with counts, delete