feat: add cJSON and SQLite amalgamation source files under deps/

Add the cJSON library (cJSON.c, cJSON.h) and SQLite amalgamation
(sqlite3.c, sqlite3.h, sqlite3ext.h, shell.c) as vendored dependencies
in the deps/ directory for use by the project build system.

example/dns_demo.wren

@@ -0,0 +1,47 @@
+// retoor <retoor@molodetz.nl>
+
+import "dns" for Dns
+
+System.print("=== DNS Module Demo ===\n")
+
+System.print("--- Basic DNS Lookup ---")
+var hostname = "example.com"
+System.print("Looking up: %(hostname)")
+var addresses = Dns.lookup(hostname)
+System.print("Addresses: %(addresses)")
+
+System.print("\n--- IPv4 Only Lookup ---")
+System.print("Looking up %(hostname) (IPv4 only)")
+var ipv4Addresses = Dns.lookup(hostname, 4)
+System.print("IPv4 addresses: %(ipv4Addresses)")
+
+System.print("\n--- IPv6 Only Lookup ---")
+System.print("Looking up %(hostname) (IPv6 only)")
+var ipv6Addresses = Dns.lookup(hostname, 6)
+System.print("IPv6 addresses: %(ipv6Addresses)")
+
+System.print("\n--- Multiple Hostname Lookups ---")
+var hosts = ["google.com", "github.com", "cloudflare.com"]
+for (host in hosts) {
+  var addrs = Dns.lookup(host, 4)
+  if (addrs.count > 0) {
+    System.print("%(host) -> %(addrs[0])")
+  } else {
+    System.print("%(host) -> (no addresses found)")
+  }
+}
+
+System.print("\n--- Localhost Lookup ---")
+var localhost = Dns.lookup("localhost", 4)
+System.print("localhost (IPv4): %(localhost)")
+
+System.print("\n--- Practical Example: Server Connection ---")
+var serverHost = "httpbin.org"
+System.print("Resolving server: %(serverHost)")
+var serverAddrs = Dns.lookup(serverHost, 4)
+if (serverAddrs.count > 0) {
+  System.print("Server IP: %(serverAddrs[0])")
+  System.print("Ready to connect to %(serverAddrs[0]):80")
+} else {
+  System.print("Could not resolve %(serverHost)")
+}