docs(eslint-plugin): add rule table to package README

The npm README had no rule listing. Add the four rules with
defaults and descriptions so users see them without visiting
the monorepo root.

Co-authored-by: Andrew <andrewxhill@gmail.com>

Author: 4ndr3wxh1ll

packages/eslint-plugin/README.md

@@ -16,6 +16,15 @@ import codecontext from "@recallnet/codecontext-eslint-plugin";
 export default [codecontext.configs.recommended];
 ```
 
+## Rules
+
+| Rule                          | Default | Description                                                     |
+| ----------------------------- | ------- | --------------------------------------------------------------- |
+| `context-hierarchy`           | error   | Type/subtype combinations must be valid                         |
+| `valid-context-refs`          | error   | Local `{@link file:...}` targets must resolve to existing files |
+| `require-context-for-complex` | warn    | Complex functions (cyclomatic > 5) should have `@context`       |
+| `no-stale-context`            | error   | Verification dates too old, or code changed without date bump   |
+
 ## Docs
 
 - Repo: https://github.com/recallnet/codecontext