fix(templates): migrate to ESLint 9 flat config format

Replace legacy .eslintrc.js with eslint.config.js across all 4 starter
templates. Upgrade eslint to ^9.0.0 and remove @types/eslint <9 resolution.

Fixes FEC-739

Author: misama-ct

application-templates/starter-typescript/package.json

@@ -92,6 +92,11 @@
   "devDependencies": {
     "@graphql-eslint/eslint-plugin": "^4.4.0"
   },
+  "pnpm": {
+    "overrides": {
+      "jest-runner-eslint>eslint": "^9.0.0"
+    }
+  },
   "resolutions": {
     "@emotion/react": "^11.14.0",
     "@emotion/styled": "^11.14.0",

application-templates/starter/package.json

@@ -90,6 +90,11 @@
   "devDependencies": {
     "@graphql-eslint/eslint-plugin": "^4.4.0"
   },
+  "pnpm": {
+    "overrides": {
+      "jest-runner-eslint>eslint": "^9.0.0"
+    }
+  },
   "resolutions": {
     "@emotion/react": "^11.14.0",
     "@emotion/styled": "^11.14.0",

custom-views-templates/starter-typescript/package.json

@@ -92,6 +92,11 @@
   "devDependencies": {
     "@graphql-eslint/eslint-plugin": "^4.4.0"
   },
+  "pnpm": {
+    "overrides": {
+      "jest-runner-eslint>eslint": "^9.0.0"
+    }
+  },
   "resolutions": {
     "@emotion/react": "^11.14.0",
     "@emotion/styled": "^11.14.0",

custom-views-templates/starter/package.json

@@ -90,6 +90,11 @@
   "devDependencies": {
     "@graphql-eslint/eslint-plugin": "^4.4.0"
   },
+  "pnpm": {
+    "overrides": {
+      "jest-runner-eslint>eslint": "^9.0.0"
+    }
+  },
   "resolutions": {
     "@emotion/react": "^11.14.0",
     "@emotion/styled": "^11.14.0",