FASE 7e: CSS Inline Extraction + Minificación

- Extraído CSS inline de 15 templates POS + 13 templates Dashboard
- CSS movido a archivos .css externos en pos/static/css/ y dashboard/
- Generados .min.css vía minify-assets.sh
- Nginx auto-serve transparente para .min.css
- Tests: 73/73 pasando
- Script: scripts/extract-inline-css.py

scripts/extract-inline-css.py

@@ -0,0 +1,110 @@
+#!/usr/bin/env python3
+"""Extract inline <style> blocks from HTML templates into external CSS files.
+
+Replaces each <style>...</style> block with a <link rel="stylesheet"> tag.
+This allows browsers to cache CSS across page navigations and dramatically
+reduces HTML payload size.
+
+Usage:
+    python3 extract-inline-css.py
+"""
+
+import glob
+import re
+from pathlib import Path
+
+
+def extract_css_from_template(html_path, css_output_dir, css_url_prefix):
+    """Extract <style> blocks from an HTML file into an external CSS file.
+
+    Returns the modified HTML content.
+    """
+    with open(html_path, 'r', encoding='utf-8') as f:
+        html = f.read()
+
+    style_blocks = list(re.finditer(
+        r'<style[^>]*>(.*?)</style>',
+        html,
+        re.DOTALL | re.IGNORECASE
+    ))
+
+    if not style_blocks:
+        return html  # No inline CSS to extract
+
+    # Extract all CSS content
+    css_parts = []
+    for m in style_blocks:
+        css = m.group(1).strip()
+        if css:
+            css_parts.append(css)
+
+    if not css_parts:
+        return html
+
+    # Write external CSS file
+    name = Path(html_path).stem
+    css_filename = f"{name}.css"
+    css_path = Path(css_output_dir) / css_filename
+    css_path.parent.mkdir(parents=True, exist_ok=True)
+
+    combined_css = '\n\n'.join(css_parts)
+    with open(css_path, 'w', encoding='utf-8') as f:
+        f.write(f"/* Extracted from {Path(html_path).name} */\n\n")
+        f.write(combined_css)
+        f.write('\n')
+
+    # Replace first <style> block with <link>, remove the rest
+    link_tag = f'<link rel="stylesheet" href="{css_url_prefix}{css_filename}">'
+    new_html = html[:style_blocks[0].start()] + link_tag + html[style_blocks[0].end():]
+
+    # Remove remaining style blocks (they were concatenated into the CSS file)
+    for m in reversed(style_blocks[1:]):
+        new_html = new_html[:m.start()] + new_html[m.end():]
+
+    return new_html
+
+
+def process_directory(html_dir, css_output_dir, css_url_prefix):
+    """Process all HTML files in a directory."""
+    templates = sorted(glob.glob(f"{html_dir}/*.html"))
+    total_saved = 0
+
+    for html_path in templates:
+        new_html = extract_css_from_template(html_path, css_output_dir, css_url_prefix)
+
+        # Write back the modified HTML
+        with open(html_path, 'w', encoding='utf-8') as f:
+            f.write(new_html)
+
+        original_size = Path(html_path).stat().st_size
+        total_saved += original_size - len(new_html.encode('utf-8'))
+        name = Path(html_path).name
+        print(f"  {name}: extracted CSS -> {css_url_prefix}{Path(html_path).stem}.css")
+
+    return total_saved
+
+
+def main():
+    print("=== Extracting inline CSS from POS templates ===")
+    saved_pos = process_directory(
+        '/home/Autopartes/pos/templates',
+        '/home/Autopartes/pos/static/css',
+        '/pos/static/css/'
+    )
+
+    print("\n=== Extracting inline CSS from Dashboard templates ===")
+    saved_dash = process_directory(
+        '/home/Autopartes/dashboard',
+        '/home/Autopartes/dashboard',
+        ''  # Dashboard CSS is in the same directory
+    )
+
+    total_saved_kb = (saved_pos + saved_dash) / 1024
+    print(f"\n=== Done ===")
+    print(f"Total HTML payload reduced by ~{total_saved_kb:.0f} KB")
+    print(f"POS templates: ~{saved_pos/1024:.0f} KB")
+    print(f"Dashboard templates: ~{saved_dash/1024:.0f} KB")
+
+
+if __name__ == '__main__':
+    main()