docs(license): apply Creative Commons licence to V1 exported site

- Add CC BY-NC-SA 4.0 licence and attribution to site footer
- Update copyright notice and author attribution across exported pages
- Regenerate V1 export assets to reflect new licensing terms
- Consolidate scripts and styles as part of the export rebuild
- Update Bootstrap Studio project file used for V1 exports

Signed-off-by: Alexander Davis <alex@adcm.uk>

export/sitemap.xml

@@ -12,6 +12,9 @@
     <url>
         <loc>https://www.computingbox.co.uk/binary.html</loc>
     </url>
+    <url>
+        <loc>https://www.computingbox.co.uk/copyright.html</loc>
+    </url>
     <url>
         <loc>https://www.computingbox.co.uk/gcse-hexadecimal.html</loc>
     </url>
@@ -21,6 +24,9 @@
     <url>
         <loc>https://www.computingbox.co.uk/</loc>
     </url>
+    <url>
+        <loc>https://www.computingbox.co.uk/legal-code.html</loc>
+    </url>
     <url>
         <loc>https://www.computingbox.co.uk/nand-gate.html</loc>
     </url>