fix: LLM analysis + new run button + settings page support

- Fixed LLM failing silently (401 auth error on every iteration)
- Reset provider to Ollama (working) from broken OpenRouter config
- Added /api/clear endpoint + 'New Run' button to reset history
- LLM failures now logged visibly with error details
- LLM suggestions persisted to iteration data (survive restarts)
- Settings page support via llm_settings.json (multi-provider)

config/llm_settings.json

@@ -0,0 +1,21 @@
+{
+  "provider": "ollama",
+  "model": "qwen3.5:27b",
+  "providers": {
+    "ollama": {
+      "base_url": "http://100.100.242.21:11434"
+    },
+    "lmstudio": {
+      "base_url": "http://100.100.242.21:1234"
+    },
+    "openai": {
+      "api_key": ""
+    },
+    "anthropic": {
+      "api_key": ""
+    },
+    "openrouter": {
+      "api_key": ""
+    }
+  }
+}