docs: update supported OS types in FAQ (#903)

[akashm011]

This PR updates the FAQ to accurately reflect the supported operating systems for both host installation and container image patching in Copa.

Changes include:

• Adding a "Host Installation" section that lists:
  • macOS – Install via Homebrew.
  • Linux – Generic Linux installations via Homebrew.
• Updating the "Container Image Patching Support" section to include:
  • DPKG-based (Debian/Ubuntu) images.
  • RPM-based images for Azure Linux 3.0+, CBL-Mariner (Azure Linux 1 & 2), CentOS, Oracle Linux, Rocky Linux, Alma Linux, and Amazon Linux.
  • Clarifying that APK-based (Alpine) images are not supported.

Closes #903.