Tracking issue from closed PR #812.

Documentation needs synchronization with code changes from version 0.16.2 release.

Changes needed

docs/quickstart.md:

• Update version example from 0.13.1 to 0.16.2

docs/usage.md:

• Add missing --enable-api-proxy flag documentation with reference to api-proxy-sidecar.md
• Add missing --allow-full-filesystem-access flag documentation with security warning
• Update Docker image examples from v0.13.0 to latest tag

Original PR: #812