Implement cat command

Author: RihannaP

implement-shell-tools/Package.json

@@ -0,0 +1,6 @@
+{
+        "type": "module",
+        "dependencies": {
+                "commander": "^14.0.1"
+        }
+}

implement-shell-tools/cat/cat.js

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+import { program } from "commander";
+import { promises as fs } from "node:fs";
+import process from "node:process";
+
+program
+    .name("cat command")
+    .description("Implementing 'cat' command")
+    .option("-n", "The line numbers")
+    .option("-b", "The line numbers only for non-empty lines")
+    .argument("<paths...>", "The file paths to process");
+
+program.parse();
+
+const paths = program.args;
+let lineNumber = 1;
+const displayLineNumber = program.opts().n;
+const displayNonEmptyLineNumber = program.opts().b;
+
+for(const path of paths){
+const content = await fs.readFile(path, "utf-8");
+const lines = content.split("\n");
+  for(const line of lines){
+    if(displayLineNumber){
+      console.log(`${String(lineNumber).padStart(6, ' ')}  ${line}`);
+      lineNumber++;
+    } else if (displayNonEmptyLineNumber) {
+      if (line.trim()) {
+        console.log(`${String(lineNumber).padStart(6, ' ')}  ${line}`);
+        lineNumber++;
+      } else {
+          console.log(line);
+
+      }
+     } 
+  }
+}