Docs: Add reproducible Unikernel examples and build documentation (Nginx, Redis, Httpreply)

[Nachiket-Roy]

Description

This PR introduces robust, reproducible build documentation and Dockerfiles for three popular unikernel applications (Nginx, Redis, and Httpreply). It significantly lowers the barrier to entry by providing users with exact steps and automated container configurations to build unikernel images via Unikraft and deploy them seamlessly over urunc.

Related issues

• Fixes Provide documentation and building steps for unikernel examples #107

How was this tested?

• Manually built all three examples from scratch using nerdctl build -t urunc--example . and docker build
• Verified that the initramfs builds for Nginx and Redis correctly compile and embed the filesystem directly into the debug kernel binaries.
• Specifically tested the Redis conditional fallback mechanism to ensure it properly catches the compilation error, applies the sed patch, leverages the kraft object cache, and successfully re-links the final binary without hanging.

LLM usage

Gemini

Checklist

• I have read the contribution guide.
• The linter passes locally (make lint).
• The e2e tests of at least one tool pass locally (make test_ctr, make test_nerdctl, make test_docker, make test_crictl).
• If LLMs were used: I have read the llm policy.

[netlify]

✅ Deploy Preview for urunc ready!

Name	Link
🔨 Latest commit	1d56db3
🔍 Latest deploy log	https://app.netlify.com/projects/urunc/deploys/6a3ae8e5fe10d50008664737
😎 Deploy Preview	https://deploy-preview-760--urunc.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[cmainas]

Hello @Nachiket-Roy ,

thank you for this PR. Unfortunately, the suggested examples and text is not what we want to have as a documentation and examples for unikernel building.

• The recommended way to build images for urunc is bunny
• The text in the examples page does not seem to add any useful information about the building process, the requirements, storage support, etc.
• As far as I know, kraftkit uses docker buildkit. Have you tried to build the dockerfiles you suggest and did they work?

[Nachiket-Roy]

Yes i did test them locally but as you say this is not the right method and i will update the PR accordingly. Thanks for the feedback.

[Nachiket-Roy]

@cmainas i have update the PR with the right way to build image i.e. bunny (update the docs accordingly) could you check if the current PR is correct or need improvement?