The plugin imports definePlugin and defineRule from oxlint (packages/oxlint-plugin-convex/src/index.ts:56), but those exports were removed from the oxlint package entry point and moved to a separate @oxlint/plugins package (oxc-project/oxc#18610, #18828). Loading the plugin fails on oxlint 1.45 and newer:

SyntaxError: The requested module 'oxlint' does not provide an export named 'definePlugin'
    at loadPlugin (.../oxlint/dist/lint.js:17515:17)

(oxlint@1.44.0 was never published to npm, so 1.45.0 is the first user-visible broken release.)

proposed fix:

- import { definePlugin, defineRule } from "oxlint";
+ import { definePlugin, defineRule } from "@oxlint/plugins";

// packages/oxlint-plugin-convex/package.json
+ "dependencies": {
+   "@oxlint/plugins": ">=1.43.0"
+ },
  "peerDependencies": {
-   "oxlint": ">=1.0.0"
+   "oxlint": ">=1.45.0"
  }

@oxlint/plugins was first published at 1.43.0, so >=1.43.0 covers all versions where the new entry point exists.