feat(console): UI improvements, bug fixes, and code quality audit

[r2dedios]

Summary

UI Enhancements

• Rename Instances → Nodes across the entire UI (sidebar, routes, components, badge map)
• Overview icons added to TopMetricCards, PartnerDonutChart, and events card; fixed oversized provider icons
• Breadcrumbs on Account, Cluster, and Node detail pages (later removed — cleaner without them)
• Table improvements: resource badges, provider icons, Cost (15d) column, improved empty state text
• Skeleton loaders replace full-viewport spinners in all table components
• Unified timestamps with relative format (HH:mm:ss - dd/MM/yyyy (2 hours ago)) across all pages
• Dynamic browser tab titles via useDocumentTitle hook on all 9 pages
• Account cost evolution chart with daily cost data on Account details page

Backend Fixes

• Daily cost endpoint (GET /accounts/:id/daily-costs) for account cost evolution charts
• Expense date handling: fix UTC boundaries in AWS Cost Explorer queries, handle both date formats from AWS responses
• DB partitions: run partition creation daily instead of weekly
• Scanner cleanup: remove dead nil check on NewExpense, fix incorrect comments on date variables

Bug Fixes (from code audit)

• useTableSort: prevent array mutation (spread copy before sort) and null crash (nullish coalescing)
• useEffect cleanup: add cancellation flags in 6 components to prevent state updates on unmounted components
• 404 route: add catch-all NotFound page with EmptyState and "Go to Dashboard" button
• Action creation modal: add try/catch error handling with PatternFly Alert feedback
• Debounce stabilization: fix unstable debounce in toolbar search inputs using useRef + useEffect + useCallback pattern

Code Quality (from code audit)

• Replace console.log with debug() utility across 5 files
• Remove dead code: commented-out Scan nav entry in SidebarNavigation
• Type safety: replace any types with proper CardContentItem / SubtitleContentItem interfaces in CardRenderer; remove blanket eslint-disable in Overview
• Page size limits: unify page_size from 100000 to 10000 in data fetching hooks
• Stable list keys: use item.name instead of array index in TopMetricCard
• ErrorBoundary: add React class-based error boundary wrapping all routes
• Fix misleading debug messages in NodeDetails and AccountDetails

Documentation

• Inline comments added to: date formatters (purpose), pagination interceptor (regex explanation with example), theme initialization (priority chain)
• GitHub issues created for larger refactorings: refactor(console): extract reusable FilterMenu component from toolbar duplications #273, refactor(console): unify duplicated ClustersTable components #274, refactor(console): standardize data fetching pattern across components #275, refactor(console): decompose AppLayout into smaller subcomponents #276, refactor(console): decompose ModalCreateAction into focused subcomponents #277

Related Issues

• refactor(console): extract reusable FilterMenu component from toolbar duplications #273 — Extract shared data-fetching logic into custom hooks
• refactor(console): unify duplicated ClustersTable components #274 — Centralize error handling with react-query
• refactor(console): standardize data fetching pattern across components #275 — Type-safe route params with shared constants
• refactor(console): decompose AppLayout into smaller subcomponents #276 — Add unit tests for utility functions
• refactor(console): decompose ModalCreateAction into focused subcomponents #277 — Add aria-labels and keyboard navigation to interactive elements

Test plan

• Sidebar shows "Nodes" instead of "Instances"
• Cost (15d) column appears in Accounts and Clusters tables with currency formatting
• Skeleton loaders appear during table data loading (no layout shift)
• Timestamps show absolute + relative format on all pages
• Browser tab title updates when navigating between pages
• Overview card icons are consistent in size
• Account cost evolution chart renders on Account details page
• Sorting tables with null values does not crash
• Navigating quickly between pages does not produce console warnings
• Invalid URL (e.g. /xyz) shows 404 page with "Go to Dashboard" button
• Creating an action with API error shows alert in modal
• Search inputs in toolbars debounce correctly without stale closures
• make console-lint passes with 0 errors