refactor: consolidate all roles into ansible/roles/ and update ansible.cfg

- Move all roles from playbooks/roles/ to roles/
- Update roles_path in ansible.cfg
- Add cast user to common role
- Create standalone podman role
- Add semaphore role with Podman + Quadlet support

ansible/roles/ollama/defaults/main.yml

@@ -0,0 +1,28 @@
+---
+# ------------------------------------------------------------------------------
+# FILE: roles/ollama/defaults/main.yml
+# ------------------------------------------------------------------------------
+
+# ROCm
+ollama_rocm_version: "6.2"     # ROCm release stream — update when upgrading
+ollama_rocm_packages:
+  - hip-runtime-amd             # Pulls in full ROCm stack
+  - rocminfo                    # GPU visibility verification tool
+  - rocm-smi-lib                # ROCm system management interface
+
+# Ollama
+ollama_version: "latest"
+ollama_port: 11434
+ollama_host: "0.0.0.0"         # Listen on all interfaces for cluster access
+ollama_default_model: "qwen3:8b"
+
+# HSA override — required for RX 5000-series (gfx1010 / RDNA 1)
+# Tells ROCm to treat the GPU as gfx1010 which has supported LLVM targets.
+ollama_hsa_override_gfx_version: "10.1.0"
+
+# Data disk
+ollama_setup_data_disk: true
+ollama_data_disk: /dev/sdb
+ollama_data_dir: /var/lib/ollama   # Ollama default models path
+ollama_data_vg: ollama-vg
+ollama_data_lv: ollama-lv