feat: add DeepSeek and NVIDIA NIM providers

- Add deepseek and nvidia entries to gateway-provider config

- Add DEEPSEEK_API_KEY and NVIDIA_API_KEY to .env.example

- Add deepseek and nvidia to doctor's LLM provider check

- Fix remaining harness-log → log-message reference

.gitignore

@@ -1,10 +1,10 @@
 .env
-opencortex-server
+passepartout-server
 \$MEMEX_DIR/
 *.log
 *~
 \#*#
-opencortex-tui
+passepartout-tui
 test_input.txt
 
 # Generated artifacts (source of truth is .org)