Changelog for Asset Modeller 26.16.0

Changes

• Add retention of AI conversations ([ai.retention] config section) (PR, #7663)
• Add speech to text for dictating AI Assistant prompts ([ai.stt] config section) (PR, #7999)
• Update all dependencies to their latest versions, resolving 11 security advisories (PR, #8005)
• Serve HTTP with Bandit instead of Cowboy, resolving the last 2 security advisories (PR, #8005)