Migrate to ESM and upgrade dependencies (#763)

* Migrate to ESM and upgrade dependencies

* Remove unused tsconfig.eslint.json

* bump version to 7.0.0 in package.json and package-lock.json

* Add ESM migration note to README for V7

* Remove unnecessary devDependencies: ts-node, @types/jest

* npm audit fix

* Update README with ESM migration details

Clarified migration details to ESM for action compatibility.

* Downgrade @types/node to ^24, clean up tsconfig and README.

Author: priyagupta108

.eslintignore

@@ -10,7 +10,10 @@ allowed:
   - cc0-1.0
   - unlicense
   - 0bsd
+  - blueoak-1.0.0
 
 reviewed:
   npm:
-     - "@actions/http-client"
+     - "@actions/http-client"
+     - "balanced-match"
+     - "brace-expansion"