Add tracked Git hooks and refactor timeline arrows

- Add .githooks directory with pre-commit hook for cv.webp generation
- Create installation script for hooks setup
- Add documentation for hooks usage
- Refactor timeline arrows into reusable commands (\timelinearrow and \timelinearrowcontinue)
- Simplify arrow usage by only requiring length parameter

.githooks/pre-commit

@@ -0,0 +1,46 @@
+#!/bin/bash
+
+# Pre-commit hook to generate cv.webp from cv.pdf
+
+# Check if cv.pdf exists and is staged
+if git diff --cached --name-only | grep -q "^cv\.pdf$"; then
+    echo "cv.pdf is being committed, generating cv.webp..."
+
+    # Generate webp from first page of PDF
+    if [ -f "cv.pdf" ]; then
+        # Use pdftoppm to convert first page to PNG, then ImageMagick to convert to WebP
+        pdftoppm -png -f 1 -l 1 -singlefile cv.pdf temp_cv && \
+        magick temp_cv.png -quality 85 img/cv.webp && \
+        rm -f temp_cv.png
+
+        if [ $? -eq 0 ]; then
+            echo "Successfully generated img/cv.webp"
+            # Add the generated image to the commit
+            git add img/cv.webp
+        else
+            echo "Warning: Failed to generate cv.webp"
+            exit 1
+        fi
+    else
+        echo "Warning: cv.pdf not found, skipping cv.webp generation"
+    fi
+elif [ -f "cv.pdf" ]; then
+    # cv.pdf exists but is not being committed, check if it's newer than cv.webp
+    if [ ! -f "img/cv.webp" ] || [ "cv.pdf" -nt "img/cv.webp" ]; then
+        echo "cv.pdf has been modified but not staged. Generating cv.webp anyway..."
+
+        pdftoppm -png -f 1 -l 1 -singlefile cv.pdf temp_cv && \
+        magick temp_cv.png -quality 85 img/cv.webp && \
+        rm -f temp_cv.png
+
+        if [ $? -eq 0 ]; then
+            echo "Successfully generated img/cv.webp"
+            git add img/cv.webp
+        else
+            echo "Warning: Failed to generate cv.webp"
+            exit 1
+        fi
+    fi
+fi
+
+exit 0