feat: add llms.txt for better LLM usage

[rothgar]

Adds the file to the root path for automatic discovery and helping LLMs discover endpoints and usage.

[Copilot]

Pull request overview

Adds an llms.txt file at the repository root to provide a concise, machine-readable description of Image Factory concepts, HTTP/PXE/OCI endpoints, and example usage for automated LLM discovery.

Changes:

• Introduces llms.txt describing core Image Factory concepts (schematics, versions, models) and a typical workflow.
• Documents key HTTP/PXE/OCI endpoints and enterprise-only APIs, with example curl/docker commands.

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[shanduur]

Do we need to write this down? It will become obsolete each time we update docs. If this is needed, maybe we can serve it from Image Factory itself on factory.talos.dev/llms.txt?

[rothgar]

Do we need to write this down? It will become obsolete each time we update docs. If this is needed, maybe we can serve it from Image Factory itself on factory.talos.dev/llms.txt?

That was the goal and I forgot to also push those changes. I just added a handler for /llms.txt with the text returned.

[rothgar]

The lint check failures are not because of this PR.

#27 ERROR: process "/bin/sh -c dis-vulncheck -tool=false ./..." did not complete successfully: exit code: 1
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 > [lint-govulncheck 2/2] RUN --mount=type=cache,target=/root/.cache/go-build,id=image-factory/root/.cache/go-build --mount=type=cache,target=/go/pkg,id=image-factory/go/pkg dis-vulncheck -tool=false ./...:
10.47 
10.47 Vulnerability #2: GO-2026-5932
10.47 The golang.org/x/crypto/openpgp package is unmaintained, unsafe by design, and has known security issues
10.47 More info: https://pkg.go.dev/vuln/GO-2026-5932
10.47 Affected products: 
10.47  - pkg:golang/golang.org%2Fx%2Fcrypto@v0.52.0
10.47 Your code is affected by this vulnerability
10.47 
10.47 
10.47 dis-vulncheck scan complete! 🚀
------
WARNING: No output specified with remote driver. Build result will only remain in the build cache. To push result image into registry use --push or to load image into docker use --load
Dockerfile:237
--------------------
 235 |     FROM base AS lint-govulncheck
 236 |     WORKDIR /src
 237 | >>> RUN --mount=type=cache,target=/root/.cache/go-build,id=image-factory/root/.cache/go-build --mount=type=cache,target=/go/pkg,id=image-factory/go/pkg dis-vulncheck -tool=false ./...
 238 |     
 239 |     # runs unit-tests with race detector
--------------------
ERROR: failed to build: failed to solve: process "/bin/sh -c dis-vulncheck -tool=false ./..." did not complete successfully: exit code: 1
make[1]: *** [Makefile:204: target-lint-govulncheck] Error 1
make[1]: Leaving directory '/home/runner/_work/image-factory/image-factory'
make: *** [Makefile:254: lint-govulncheck] Error 2

[shanduur]

Can we render this on build? This is technically just a docs/API.md with some minor changes, right?

[rothgar]

Yes, it's just a raw text endpoint. I'm not sure what the difference would be with rendering on build vs embedding. Happy to do it a different way, I just wanted something that was easier for discovery and usage.