Remove use of shebang

- Removed shebang line from generate and clear scripts
- Added `.js` extension to generate and clear script files
- Updated scripts in `package.json` accordingly

scripts/clear.js

@@ -0,0 +1,27 @@
+const fs = require("fs");
+const path = require("path");
+
+const src_path = path.join(__dirname, "..", "src");
+
+try {
+    fs.readdirSync(src_path).
+        filter(f => {
+            if (f.includes("day")) {
+                console.log("found", f);
+                return true;
+            }
+            console.log("ignoring", f);
+            return false;
+        }).
+        forEach(f => {
+            const file = path.join(src_path, f);
+            console.log("deleting", file);
+            fs.rmSync(file, {
+                recursive: true,
+                force: true,
+            });
+        });
+} catch (e) { console.log(e); }
+
+
+