#33 Packages updates and fixes

Summary by cubic

Bumps dependency security floors, adds dependency auditing to CI, and switches the autocomplete endpoint in preparation for the 1.10.0 release.

• Autocomplete now calls the canonical /search/autocomplete endpoint; the legacy bare-list and suggestions-key response shapes remain supported.
• Suggestion now models type and count from the compact search entries; domain_ids and the deprecated domains alias are unchanged.
• Pins security floors for anyio, certifi, aiohttp, multidict, and urllib3 to exclude compromised CA bundles and known vulnerable versions.
• pip-audit runs on every locked dependency across Python 3.10–3.13 in CI, and Dependabot groups minor/patch and security updates weekly.