refactor(ssh): consolidate real_ssh into ssh, remove duplication

real_ssh was a separate service name pointing to the same template and
behaviour as ssh. Merged them: ssh is now the single real-OpenSSH service.

- Rename templates/real_ssh/ → templates/ssh/
- Remove decnet/services/real_ssh.py
- Deaddeck archetype updated: services=["ssh"]
- Merge test_real_ssh.py into test_ssh.py (includes deaddeck + logging tests)
- Drop decnet.services.real_ssh from test_build module list

development/DEVELOPMENT.md

@@ -4,7 +4,7 @@
 *Goal: Ensure every service is interactive enough to feel real during manual exploration.*
 
 ### Remote Access & Shells
-- [x] **SSH (Cowrie)** — Custom filesystem, realistic user database, and command execution.
+- [ ] **SSH (Cowrie)** — Custom filesystem, realistic user database, and command execution.
 - [ ] **Telnet (Cowrie)** — Realistic banner and command emulation.
 - [ ] **RDP** — Realistic NLA authentication and screen capture (where possible).
 - [ ] **VNC** — Realistic RFB protocol handshake and authentication.