* feat: Add subcategory breakdown to Cash Flow and Reports
Implements Discussion #546 - adds hierarchical category/subcategory
visualization to both the Sankey chart and Reports breakdown tables.
Sankey chart changes:
- Income: subcategory → parent category → Cash Flow
- Expense: Cash Flow → parent category → subcategory
- Extracted process_category_totals helper to DRY up income/expense logic
Reports breakdown changes:
- Subcategories display nested under parent categories
- Smaller dots and indented rows for visual hierarchy
- Extracted _breakdown_table partial to eliminate duplication
* fix: Dynamic node padding for Sankey chart with many nodes
- Add dynamic nodePadding calculation to prevent padding from dominating
chart height when there are many subcategory nodes
- Extract magic numbers to static constants for configuration
- Decompose monolithic #draw() into focused methods
- Consolidate duplicate tooltip/currency formatting code
- Modernize syntax with spread operators and optional chaining
* fix: Hide overlapping Sankey labels, show on hover
- Add label overlap detection by grouping nodes by column depth
- Hide labels that would overlap with adjacent nodes
- Show hidden labels on hover (node rectangle or connected links)
- Add hover events to node rectangles (not just text)
* fix: Use deterministic fallback colors for categories
- Replace Category::COLORS.sample with Category::UNCATEGORIZED_COLOR
for income categories in Sankey chart (was producing different colors
on each page load)
- Add nil color fallback in reports_controller for parent and root
categories
Addresses CodeRabbit review feedback.
* fix: Expand CSS variable map for d3 color manipulation
Add hex mappings for commonly used CSS variables so d3 can manipulate
opacity for gradients and hover effects:
- var(--color-destructive) -> #EC2222
- var(--color-gray-400) -> #9E9E9E
- var(--color-gray-500) -> #737373
* test: Add tests for subcategory breakdown in dashboard and reports
- Test dashboard renders Sankey chart with parent/subcategory transactions
- Test reports groups transactions by parent and subcategories
- Test reports handles categories with nil colors
- Use EntriesTestHelper#create_transaction for cleaner test setup
* Fix lint: use Number.NEGATIVE_INFINITY
* Remove obsolete nil color test
Category model now validates color presence, so nil color categories
cannot exist. The fallback handling in reports_controller is still in
place but the scenario is unreachable.
* Update reports_controller.rb
* FIX trade category
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Co-authored-by: sokie <sokysrm@gmail.com>
