Remove managed student assumptions from Lab 3 terminal

docs/lab3-terminal-deployment.md

@@ -6,19 +6,16 @@ Default runtime config:
 
 ```json
 {
-  "lab3TerminalUrl": "http://127.0.0.1:7681/wetty",
-  "lab3Username": "student",
-  "lab3WorkingDirectory": "/home/student/lab3"
+  "lab3TerminalUrl": "http://127.0.0.1:7681/wetty"
 }
 ```
 
 ## Runtime Contract
 
-- Create a managed `student` Unix account
 - Bind `sshd` to `127.0.0.1:22` only
 - Run WeTTY on the lab host and expose it to the browser at `/wetty`
-- Point WeTTY at localhost SSH without pre-setting the username so students see a login prompt
-- Start students in `/home/student/lab3`
+- Point WeTTY at localhost SSH without pre-setting the username so users see a normal login prompt
+- Let the host control which existing local accounts are allowed to sign in
 
 Example launch command:
 
@@ -29,7 +26,7 @@ wetty --host 0.0.0.0 --port 7681 --base /wetty --allow-iframe --ssh-host 127.0.0
 ## Linux / WSL Shape
 
 - Install `openssh-server`
-- Restrict `sshd` to `127.0.0.1` and the managed `student` account
+- Restrict `sshd` to `127.0.0.1`
 - Install WeTTY with the managed Node runtime
 - Generate `/courseware-runtime.json` from deployment-time values
 - Start the wiki and WeTTY as separate managed services