docs: refine footer branding and improve Javadoc overview

- remove Material for MkDocs generator branding from the site footer
- keep footer presentation aligned with the project's professional documentation style
- improve Javadoc overview content for the API landing page
- align Javadoc introductory text with the main project site messaging
- clarify project scope, documentation purpose, and license information

mkdocs.yml

@@ -3,7 +3,7 @@ site_description: High-performance multi-language stemming toolkit for Java
 site_url: https://leogalambos.github.io/Radixor/
 repo_url: https://github.com/leogalambos/Radixor
 repo_name: leogalambos/Radixor
-copyright: "&copy; ${year} Egothor. Licensed under <a href='https://github.com/leogalambos/Radixor/blob/main/LICENSE'>BSD-3-Clause</a>."
+copyright: "&copy; 2026 Egothor. Licensed under <a href='https://github.com/leogalambos/Radixor/blob/main/LICENSE'>BSD-3-Clause</a>."
 
 theme:
   name: material
@@ -20,6 +20,9 @@ theme:
       primary: indigo
       accent: indigo
 
+extra: 
+  generator: false
+
 markdown_extensions:
   - admonition
   - attr_list