feat(eslint-plugin): implement no-typeof-runtype rule

[M-jerez]

Summary

Implements the initial functionality for the ESLint plugin package with a no-typeof-runtype rule that detects when runType<typeof ...>() is used and reports an ESLint error.

Background

The run-types package has special functions that extract metadata from types at compile-time. The main function is runType from the '@mionkit/run-types' package. This is a generic function that returns metadata for a type, but it only works with explicitly defined types and most of the time does not infer types correctly when typeof is used.

Changes

✅ ESLint Rule Implementation

• Rule: no-typeof-runtype detects runType<typeof ...>() usage
• Smart Detection: Only flags runType from @mionkit/run-types package (not other functions with same name)
• Import Support: Works with both package imports (@mionkit/run-types) and relative imports (../../lib/runType)
• Error Message: Provides clear guidance to use explicit type definitions instead

✅ Comprehensive Testing

• 13 test cases covering valid and invalid usage patterns
• Tests for package imports, relative imports, union types, and edge cases
• All tests passing ✅

✅ Build Configuration

• Fixed Jest configuration to work with lib/ directory structure
• Updated build scripts for proper CommonJS compilation
• Package builds successfully ✅

✅ Validation

• Successfully detects 3 violations in packages/run-types/src/runType/atomic/literal.spec.ts:
  • Line 15: const rtReg = runType<typeof reg>();
  • Line 16: const rtReg2 = runType<typeof reg2>();
  • Line 19: const rtSym = runType<typeof sym>();

Example

❌ Before (problematic):

import {runType} from '@mionkit/run-types';

type User = {name:string, age:number};
const user: User = {name: 'John', age: 34};

const wrongRtUser = runType<typeof user>(); // ❌ ESLint error

✅ After (correct):

import {runType} from '@mionkit/run-types';

type User = {name:string, age:number};
const user: User = {name: 'John', age: 34};

const rtUser = runType<User>(); // ✅ OK

Testing

cd packages/eslint-plugin
npm test  # All 13 tests pass ✅
npm run build  # Builds successfully ✅

Next Steps

This PR provides the foundation for the ESLint plugin. Future enhancements could include:

• Adding the rule to root ESLint configuration (when plugin is published)
• Additional rules for router functions type safety
• Integration with CI/CD pipeline

---

Pull Request opened by Augment Code with guidance from the PR author