feat: F4.6g1 the echo server and the generic client windows

Oracle EchoWindowRun uses Java's echo server and client windows as a
person does; SaveAfterRunRun echo saves what Java keeps after the run.
The room takes setActive with a port, connect/disconnect/send, sends
both views and writes the server's port and the client's target back.
The editor's windows show Java's buttons, fields and lines; a port that
is no port is marked and not handed over (Java's button throws).
Core fix: an empty message (one empty segment with the push, as Java's
erstelleSegmente makes) counted as a repeat and never arrived.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/editor/src/i18n/en.json

@@ -59,6 +59,10 @@
   "dhcp.static": "Static Address Assignment",
   "dhcp.subnetMask": "Netmask",
   "dhcp.upperBound": "Upper bound of address",
+  "echoServer.log": "Output",
+  "echoServer.port": "Port:",
+  "echoServer.start": "Start",
+  "echoServer.stop": "Stop",
   "emailClient.account": "Account",
   "emailClient.accountHint": "Manage email account",
   "emailClient.accountInvalid": "Wrong or incomplete data!",
@@ -293,6 +297,21 @@
   "sheet.title": "Settings",
   "sheet.wireless": "Wireless (Wi-Fi)",
   "sim.failed": "The simulation ran into an error and was stopped.",
+  "simpleClient.address": "Server address:",
+  "simpleClient.connect": "Connect",
+  "simpleClient.connected": "Connection established",
+  "simpleClient.connectionClosed": "Socket to {address} disconnected",
+  "simpleClient.disconnect": "Disconnect",
+  "simpleClient.disconnected": "Disconnected",
+  "simpleClient.failure.failed": "Active opening of socket failed.",
+  "simpleClient.failure.timedOut": "Timeout while connecting",
+  "simpleClient.failure.unresolved": "Target does not exist!",
+  "simpleClient.message": "Message:",
+  "simpleClient.notConnected": "Error while connecting",
+  "simpleClient.output": "Output",
+  "simpleClient.port": "Server port:",
+  "simpleClient.receiveFailed": "No connection established!",
+  "simpleClient.send": "Send",
   "terminal.commands": "Commands",
   "terminal.ctrlC": "Ctrl+C",
   "terminal.input": "Enter a command",