Support Podman fallback when Docker is unavailable

[nezhar]

Updates the Podman integration instructions in the docs/quickstart.md file to clarify how to use VibePod with Podman. The documentation now provides clearer steps for configuring Podman's Docker-compatible API socket and starting the user socket.

[augmentcode]

🤖 Augment PR Summary

Summary: Adds automatic Podman fallback when the default Docker connection is unavailable, improving out-of-the-box UX on systems using Podman.

Changes:

• Tries the normal Docker SDK environment connection first, then falls back to several common Podman socket paths when DOCKER_HOST is not set.
• Centralizes Podman socket candidate selection and formats clearer, actionable error hints when neither Docker nor Podman is reachable.
• Updates Quickstart docs and adds a unit test covering the fallback-to-rootless-Podman-socket behavior.

Technical Notes: Fallback candidates include $XDG_RUNTIME_DIR/podman/podman.sock, /run/user/<uid>/podman/podman.sock, and /run/podman/podman.sock; errors aggregate failed socket attempts before appending guidance.

_{🤖 Was this summary useful? React with 👍 or 👎}

[augmentcode]

Review completed. No suggestions at this time.

Comment augment review to trigger a new review at any time.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: caab744b56

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".