fix: correct intro text position and styling to match original CV

User reported intro text was in wrong position (inside Training section).

Changes:
- Moved intro text INSIDE cv-header-left div (GREEN BOX position)
- Positioned right after "20 years of experience"
- Removed duplicate Training section that showed summary
- NO section heading - just the text flowing naturally

CSS Updates:
- Removed .cv-excerpt and .excerpt-text (wrong implementation)
- Added .intro-text with exact styling from old React CV:
  * Font: Quicksand, 1.0em
  * Line height: 1.6
  * Text align: justify
  * Style: italic
  * Margin-top: 20px
  * Color: rgb(51, 51, 51)
- Added responsive styles for mobile (0.9em, 15px margin)

Verified with Playwright analysis of old React CV.
Intro text now appears exactly as in original implementation.

static/css/main.css

@@ -323,20 +323,14 @@ a:hover {
     margin: 0;
 }
 
-/* Intro/Excerpt Text */
-.cv-excerpt {
-    margin-top: 1.5rem;
-    padding: 1rem 0;
-    border-top: 1px solid #e0e0e0;
-    border-bottom: 1px solid #e0e0e0;
-}
-
-.excerpt-text {
+/* Intro/Excerpt Text - Positioned inside header, matching old React CV */
+.intro-text {
     font-family: 'Quicksand', sans-serif;
-    font-size: 0.95em;
+    font-size: 1.0em;
     line-height: 1.6;
     color: rgb(51, 51, 51);
-    margin: 0;
+    margin-top: 20px;
+    text-align: justify;
     font-style: italic;
 }
 
@@ -629,6 +623,11 @@ footer {
         align-items: flex-start;
         gap: 0.25rem;
     }
+
+    .intro-text {
+        font-size: 0.9em;
+        margin-top: 15px;
+    }
 }
 
 .no-print {}