Refactor LLM configuration to remove llamacpp support

- Removed references to llamacpp from configuration files, scripts, and documentation, streamlining the LLM setup process to focus solely on Ollama.
- Updated environment variables and paths to eliminate llamacpp-related entries, ensuring clarity in the configuration.
- Adjusted CLI commands and help messages to reflect the removal of llamacpp, enhancing user experience and reducing confusion.
- Revised documentation to provide clear guidance on using Ollama exclusively, including updates to setup instructions and runtime options.

src/gpu_rent/remote/bootstrap.sh

@@ -108,8 +108,7 @@ mkdir -p \
   "${DATA_ROOT}/Extensions" \
   "${DATA_ROOT}/DLNodes" \
   "${DATA_ROOT}/CustomWorkflows" \
-  "${DATA_ROOT}/ollama" \
-  "${DATA_ROOT}/llamacpp/models"
+  "${DATA_ROOT}/ollama"
 
 # LLM-only: data disk + tools, no SwarmUI clone / unit.
 if [[ "${GPU_RENT_SKIP_SWARMUI:-0}" == "1" ]]; then