allow multidoc yaml and expose document count to predicates

[laverya]

• [x] If any changes have been made to /project files, the corresponding /src files have been regenerated (make project-import PROJECT=<project-name>).
• [x] If any changes need to be deployed, the version has been bumped in package.json.
• [x] If any changes impact the replicated-lint package, they have been added to CHANGELOG.

[dexhorthy]

Stepping up a level -- part of the reason we made it easy to write new rules was so that clients that had more context (e.g. scheduler, features enabled, external registry tags) could bake that context into additional rules outside the core ruleset at linting time.

Rather than "add more context/variables onto the linter object so it can do deeper evaluations" why not have the client, e.g. vendor web, inject two or three additional rules based on it's understanding of the world.

In the grand scheme of things, clients should describe policy, and the linter should just enforce it. The fact that the core replicated YAML ruleset lives in this repo feels like a side effect of how things were built/designed on the fly during rules implementation. Ideally they could all move to projects

[dexhorthy]

Wrong button whoops, didn't mean to close