Move packagist check to a Haskell binary

slackbuilder.cabal

@@ -0,0 +1,40 @@
+cabal-version:      2.4
+name:               slackbuilder
+version:            0.1.0.0
+
+-- A short (one-line) description of the package.
+-- synopsis:
+
+-- A longer description of the package.
+-- description:
+
+bug-reports: https://git.caraus.tech/OSS/slackbuilder/issues
+
+license: MPL-2.0
+license-files: LICENSE
+copyright: (c) 2023 Eugen Wissner
+
+author: Eugen Wissner
+maintainer: belka@caraus.de
+
+category: Build
+extra-source-files: CHANGELOG.md
+
+executable slackbuilder
+    main-is:          Main.hs
+
+    -- Modules included in this executable, other than Main.
+    -- other-modules:
+
+    default-extensions:
+        OverloadedStrings
+        TemplateHaskell
+    build-depends:
+        aeson ^>= 2.2.0,
+        base ^>= 4.16.4.0,
+        req ^>=3.13,
+        text ^>= 2.0,
+        unordered-containers ^>= 0.2.19,
+        vector ^>= 0.13.0
+    hs-source-dirs:   app
+    default-language: Haskell2010