feat: add networking module with TCP Socket/Server and example applications

Implement a full-featured `net` module supporting TCP `Socket` and `Server` classes via libuv, including example applications (chat server, echo server, HTTP client/server, file explorer, system dashboard) and benchmark scripts (fibonacci, n-body). Add GEMINI.md project documentation and Stderr class to io module.

example/file_explorer.wren

@@ -0,0 +1,57 @@
+// retoor <retoor@molodetz.nl>
+import "io" for Directory, File, Stat
+
+class FileExplorer {
+  static listRecursive(path, depth) {
+    var indent = "  " * depth
+    var files = []
+    
+    // We wrap Directory.list in a try to handle permission errors
+    var fiber = Fiber.new {
+      files = Directory.list(path)
+    }
+    fiber.try()
+    
+    if (fiber.error != null) {
+      System.print("\%(indent)[!] Error accessing \%(path)")
+      return
+    }
+
+    // Sort files manually since String comparison isn't built-in
+    files.sort(Fn.new {|a, b|
+      var ba = a.bytes
+      var bb = b.bytes
+      var len = ba.count < bb.count ? ba.count : bb.count
+      for (i in 0...len) {
+        if (ba[i] < bb[i]) return true
+        if (ba[i] > bb[i]) return false
+      }
+      return ba.count < bb.count
+    })
+
+    for (file in files) {
+      if (file == "." || file == "..") continue
+      
+      var fullPath = path + "/" + file
+      if (path == ".") fullPath = "./" + file
+
+      var stat = Stat.path(fullPath)
+      if (stat.isDirectory) {
+        System.print("\%(indent)[D] \%(file)/")
+        listRecursive(fullPath, depth + 1)
+      } else {
+        var size = stat.size
+        var unit = "B"
+        if (size > 1024) {
+          size = size / 1024
+          unit = "KB"
+        }
+        System.print("\%(indent)[F] \%(file) (\%(size.round)\%(unit))")
+      }
+    }
+  }
+}
+
+System.print("Recursive directory listing for current path:")
+System.print("--------------------------------------------")
+FileExplorer.listRecursive(".", 0)