feat: add highlights filter button to reading progress filters

- Add 'highlighted' filter type to ReadingProgressFilterType
- New filter button with yellow highlighter icon
- Filter shows only articles that have highlights
- Highlights filter checks both eventReference and urlReference tags
- Color-coded: green for completed, yellow for highlighted, blue for others
- Applies to reads and links tabs in /me page

src/components/Me.tsx

@@ -44,7 +44,7 @@ interface MeProps {
 type TabType = 'highlights' | 'reading-list' | 'reads' | 'links' | 'writings'
 
 // Valid reading progress filters
-const VALID_FILTERS: ReadingProgressFilterType[] = ['all', 'unopened', 'started', 'reading', 'completed']
+const VALID_FILTERS: ReadingProgressFilterType[] = ['all', 'unopened', 'started', 'reading', 'completed', 'highlighted']
 
 const Me: React.FC<MeProps> = ({ 
   relayPool, 
@@ -481,8 +481,8 @@ const Me: React.FC<MeProps> = ({
   const groups = groupIndividualBookmarks(filteredBookmarks)
 
   // Apply reading progress filter
-  const filteredReads = filterByReadingProgress(reads, readingProgressFilter)
-  const filteredLinks = filterByReadingProgress(links, readingProgressFilter)
+  const filteredReads = filterByReadingProgress(reads, readingProgressFilter, highlights)
+  const filteredLinks = filterByReadingProgress(links, readingProgressFilter, highlights)
   const sections: Array<{ key: string; title: string; items: IndividualBookmark[] }> = 
     groupingMode === 'flat'
       ? [{ key: 'all', title: `All Bookmarks (${filteredBookmarks.length})`, items: filteredBookmarks }]

src/components/ReadingProgressFilters.tsx

@@ -1,9 +1,9 @@
 import React from 'react'
 import { FontAwesomeIcon } from '@fortawesome/react-fontawesome'
-import { faBookOpen, faCheckCircle, faAsterisk } from '@fortawesome/free-solid-svg-icons'
+import { faBookOpen, faCheckCircle, faAsterisk, faHighlighter } from '@fortawesome/free-solid-svg-icons'
 import { faEnvelope, faEnvelopeOpen } from '@fortawesome/free-regular-svg-icons'
 
-export type ReadingProgressFilterType = 'all' | 'unopened' | 'started' | 'reading' | 'completed'
+export type ReadingProgressFilterType = 'all' | 'unopened' | 'started' | 'reading' | 'completed' | 'highlighted'
 
 interface ReadingProgressFiltersProps {
   selectedFilter: ReadingProgressFilterType
@@ -16,15 +16,23 @@ const ReadingProgressFilters: React.FC<ReadingProgressFiltersProps> = ({ selecte
     { type: 'unopened' as const, icon: faEnvelope, label: 'Unopened' },
     { type: 'started' as const, icon: faEnvelopeOpen, label: 'Started' },
     { type: 'reading' as const, icon: faBookOpen, label: 'Reading' },
-    { type: 'completed' as const, icon: faCheckCircle, label: 'Completed' }
+    { type: 'completed' as const, icon: faCheckCircle, label: 'Completed' },
+    { type: 'highlighted' as const, icon: faHighlighter, label: 'Highlighted' }
   ]
 
   return (
     <div className="bookmark-filters">
       {filters.map(filter => {
         const isActive = selectedFilter === filter.type
-        // Only "completed" gets green color, everything else uses default blue
-        const activeStyle = isActive && filter.type === 'completed' ? { color: '#10b981' } : undefined
+        // Only "completed" gets green color, "highlighted" gets yellow, everything else uses default blue
+        let activeStyle: Record<string, string> | undefined = undefined
+        if (isActive) {
+          if (filter.type === 'completed') {
+            activeStyle = { color: '#10b981' } // green
+          } else if (filter.type === 'highlighted') {
+            activeStyle = { color: '#fde047' } // yellow
+          }
+        }
         
         return (
           <button

src/utils/readingProgressUtils.ts

@@ -1,16 +1,35 @@
 import { ReadItem } from '../services/readsService'
 import { ReadingProgressFilterType } from '../components/ReadingProgressFilters'
+import { Highlight } from '../types/highlights'
 
 /**
  * Filters ReadItems by reading progress
  */
 export function filterByReadingProgress(
   items: ReadItem[],
-  filter: ReadingProgressFilterType
+  filter: ReadingProgressFilterType,
+  highlights?: Highlight[]
 ): ReadItem[] {
+  // Build a map of article references to highlight count
+  const articleHighlightCount = new Map<string, number>()
+  if (highlights) {
+    highlights.forEach(h => {
+      if (h.eventReference) {
+        const count = articleHighlightCount.get(h.eventReference) || 0
+        articleHighlightCount.set(h.eventReference, count + 1)
+      }
+      if (h.urlReference) {
+        const count = articleHighlightCount.get(h.urlReference) || 0
+        articleHighlightCount.set(h.urlReference, count + 1)
+      }
+    })
+  }
+
   return items.filter((item) => {
     const progress = item.readingProgress || 0
     const isMarked = item.markedAsRead || false
+    const hasHighlights = (articleHighlightCount.get(item.id) || 0) > 0 || 
+                         (item.url && (articleHighlightCount.get(item.url) || 0) > 0)
     
     switch (filter) {
       case 'unopened':
@@ -21,6 +40,8 @@ export function filterByReadingProgress(
         return progress > 0.10 && progress <= 0.94 && !isMarked
       case 'completed':
         return progress >= 0.95 || isMarked
+      case 'highlighted':
+        return hasHighlights
       case 'all':
       default:
         return true