Migrated to Manifest V3 (from Manifest V2).

• Updated manifest_version to 3
• Replaced deprecated applications key with browser_specific_settings
• Added required data_collection_permissions field (this extension collects no user data)
• Removed a stale, unused web_accessible_resources entry
• Updated dependencies (wavedrom, eslint, build tooling)

No changes to functionality: the extension still detects WaveDrom JSON code blocks in <pre> elements on github.com, gitlab.com, and ieee.org, and renders them as SVG timing diagrams inline.