fix(test): resolve test runner issues and type errors

- Fix rootPath resolution in test runner (scripts/ -> project root)
- Fix TypeScript errors in maintained-node-versions immutability tests
- Refactor validation scripts for cleaner imports and error handling

Author: jdalton

scripts/test/main.mjs

@@ -37,7 +37,7 @@ process.on('unhandledRejection', (reason, _promise) => {
 })
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url))
-const rootPath = path.resolve(__dirname, '..')
+const rootPath = path.resolve(__dirname, '../..')
 const nodeModulesBinPath = path.join(rootPath, 'node_modules', '.bin')
 
 const tsconfigPath = '.config/tsconfig.check.json'

scripts/validate/external-esm-cjs.mjs

@@ -14,8 +14,7 @@
 import { createRequire } from 'node:module'
 import { readdirSync } from 'node:fs'
 import path from 'node:path'
-import { fileURLToPath } from 'node:url'
-import { pathToFileURL } from 'node:url'
+import { fileURLToPath, pathToFileURL } from 'node:url'
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url))
 const externalDir = path.resolve(__dirname, '..', '..', 'dist', 'external')
@@ -46,7 +45,7 @@ function getJsFilesRecursive(dir, files = []) {
         getJsFilesRecursive(fullPath, files)
       }
     }
-  } catch (_error) {
+  } catch {
     // Directory might not be accessible
   }
 

scripts/validate/external-exports.mjs

@@ -53,7 +53,7 @@ function getExternalModules(dir) {
         }
       }
     }
-  } catch (_error) {
+  } catch {
     // External directory might not exist in some build states
     return []
   }

test/unit/maintained-node-versions.test.ts

@@ -111,25 +111,33 @@ describe('maintained-node-versions', () => {
   describe('immutability', () => {
     it('should not allow modification of array elements', () => {
       expect(() => {
-        maintainedNodeVersions[0] = '99.99.99'
+        // Testing runtime immutability (readonly array)
+        const arr = maintainedNodeVersions as any
+        arr[0] = '99.99.99'
       }).toThrow()
     })
 
     it('should not allow push', () => {
       expect(() => {
-        maintainedNodeVersions.push('99.99.99')
+        // Testing runtime immutability (readonly array)
+        const arr = maintainedNodeVersions as any
+        arr.push('99.99.99')
       }).toThrow()
     })
 
     it('should not allow pop', () => {
       expect(() => {
-        maintainedNodeVersions.pop()
+        // Testing runtime immutability (readonly array)
+        const arr = maintainedNodeVersions as any
+        arr.pop()
       }).toThrow()
     })
 
     it('should not allow modification of named properties', () => {
       expect(() => {
-        maintainedNodeVersions.current = '99.99.99'
+        // Testing runtime immutability (readonly properties)
+        const obj = maintainedNodeVersions as any
+        obj.current = '99.99.99'
       }).toThrow()
     })
   })