Dynamic docs versions and auto search index

Switch default version handling to detect the latest docs version and expose available versions to the view. Added getLatestVersion() and getAvailableVersions() helpers and wired availableVersions into the select in index.cfm (replacing hard-coded options). Improved search index generation and maintenance: ensureSearchIndexExists now triggers generateSearchIndexForVersion when needed, and generateSearchIndexForVersion contains enhanced HTML cleaning, title/body extraction, SEO-friendly URL generation, and safe writing to files/<version>/guides/search_index.json. Miscellaneous whitespace/formatting fixes and path normalization updates.

Author: zainforbjs