Fix dashboard hydration and archive theming

openspec/specs/monthly-dashboard/spec.md

@@ -0,0 +1,40 @@
+## Purpose
+
+TBD
+
+## Requirements
+
+### Requirement: Dashboard shows month-specific financial totals
+The system SHALL return month-specific dashboard data for a requested `YYYY-MM` month using the local machine timezone for month boundaries.
+
+#### Scenario: Dashboard totals are calculated for a populated month
+- **WHEN** the user requests the dashboard for a month with expenses and paychecks
+- **THEN** the system returns total expenses, total paychecks, net cash flow, and a category breakdown for that month
+
+#### Scenario: Dashboard supports partial current-month data
+- **WHEN** the user requests the dashboard for the current month before the month is complete
+- **THEN** the system returns meaningful month-to-date totals and comparisons using the transactions recorded so far
+
+### Requirement: Dashboard includes derived spending comparisons
+The system SHALL provide derived comparisons for the selected month, including highest category, largest expense, average daily spend, and paycheck coverage information.
+
+#### Scenario: Derived comparisons are available
+- **WHEN** the selected month contains enough data for comparisons
+- **THEN** the system returns the highest category, largest single expense, average daily spend, and spend-versus-paycheck coverage values
+
+#### Scenario: Derived comparisons degrade safely for sparse data
+- **WHEN** the selected month has no expenses or otherwise insufficient data for a comparison
+- **THEN** the system returns null or empty-safe comparison fields instead of failing
+
+## ADDED Requirements
+
+### Requirement: Monthly dashboard UI renders correctly in both themes
+The system SHALL render dashboard sections, insight cards, category bars, stat tiles, and empty states with readable contrast in both light and dark themes.
+
+#### Scenario: Dashboard renders in dark mode
+- **WHEN** the user opens the dashboard while dark mode is active
+- **THEN** the summary cards, comparison cards, progress bars, and empty states use dark-compatible colors and remain readable
+
+#### Scenario: Dashboard renders in light mode
+- **WHEN** the user opens the dashboard while light mode is active
+- **THEN** the summary cards, comparison cards, progress bars, and empty states use light-compatible colors and remain readable