Add AI Cordon Picket integration

[mihail-gribov]

Two Haystack components from aicordon-haystack, one for each place a pipeline holds text a model is about to read:

• PromptInjectionFilter (preprocessors) checks documents at ingest, before chunking and embedding;
• PromptInjectionGuard (validators) checks the message list on its way into the generator, and routes a flagged exchange to a blocked socket instead of calling the model.

The check is a local rule base - no GPU, no network, no API key, no dependencies beyond aicordon. Measured on the pipeline rather than on the detector, with the numbers and the harness in the package README.

Card follows the schema in this repo's README: one card per package, pypi and repo both resolve.

[vercel]

@mihail-gribov is attempting to deploy a commit to the deepset Team on Vercel.

A member of the Team first needs to authorize it.