Part of #18610.
Our intent is to move `definePlugin`, `defineRule`, and `eslintCompatPlugin` to a separate package `@oxlint/plugins` (plural to avoid confusion with naming convention for plugins `oxlint-plugin-xxx`).
So rename the current entry point which exports these functions from `oxlint/plugin` to `oxlint/plugins` (plural).
As we prepare for alpha release of JS plugins, it feels like we can remove the warning logged to stderr.
```
WARNING: JS plugins are experimental and not subject to semver.
Breaking changes are possible while JS plugins support is under development.
```
They do still remain experimental, but I don't think we need to shout that quite as loudly now.
This is technically breaking (only for types), but custom plugins are experimental.
The ruletester/defineRule/definePlugin are re-exported but with a `@deprecated` tag which I think is a good enough trade off
I want to avoid users bringing in a ton of custom plugin code when doing `import { defineConfig } from 'oxlint'`
This ensures that we print the expected number of rules for users that are using JS Plugins.
Fix#17519.
Based on #17517, because otherwise we'd end up with weird snapshot differences when trying to merge these anyway.
AI Disclosure: The fix here was generated with Copilot + GitHub's Raptor mini model.
For a while, we've been skipping the printing of rule runs unless `--disable-nested-config` was passed. This was a result of the nested_configs value including the base config (see #16356). When we were checking whether that value was empty, it would always have at least 1 item (unless nested configs were entirely disabled).
As part of this, I've updated some configs in the fixtures to disable correctness rules, otherwise we will end up with a bunch of fixture snapshots needing updates every time a new default rule is added.
It's probably easiest to review this one commit at a time.
Pure refactor of tests. Shorten fixture directory names. There's no need to include "custom_plugin" in dir names. *All* these tests are for custom plugins.
This PR doesn't alter content of any files, just renames them.
overlookmotel