fix: remove Highlights title and count from panel, fix markdown rendering

- Remove 'Highlights' text and count number to save space in panel
- Fix markdown rendering fallback to always show content when finalHtml is not ready
- Simplify render logic by removing highlight count condition that prevented content display

src/components/ContentPanel.tsx

@@ -190,7 +190,7 @@ const ContentPanel: React.FC<ContentPanelProps> = ({
             className={markdown ? "reader-markdown" : "reader-html"} 
             dangerouslySetInnerHTML={{ __html: finalHtml }} 
           />
-        ) : markdown && relevantHighlights.length === 0 ? (
+        ) : markdown ? (
           <div 
             ref={contentRef} 
             className="reader-markdown"

src/components/HighlightsPanel.tsx

@@ -122,11 +122,6 @@ export const HighlightsPanel: React.FC<HighlightsPanelProps> = ({
   return (
     <div className="highlights-container">
       <div className="highlights-header">
-        <div className="highlights-title">
-          <FontAwesomeIcon icon={faHighlighter} />
-          <h3>Highlights</h3>
-          {!loading && <span className="count">({filteredHighlights.length})</span>}
-        </div>
         <div className="highlights-actions">
           {onHighlightVisibilityChange && (
             <div className="highlight-level-toggles">