Add LLM configuration and MCP server management UI and backend functionality

- Implemented a new SPA page for LLM Bridge and MCP Server settings in `llm-config.js`.
- Added functionality for managing LLM and MCP configurations, including toggling, saving settings, and testing connections.
- Created HTTP endpoints in `llm_utils.py` for handling LLM chat, status checks, and MCP server configuration.
- Integrated model fetching from LaRuche and Ollama backends.
- Enhanced error handling and logging for better debugging and user feedback.

web/i18n/en.json

@@ -1249,5 +1249,66 @@
   "loki.quick_placeholder": "Quick type text here...",
   "loki.quick_send": "Type",
   "loki.quick_sent": "Text sent to target",
-  "loki.quick_error": "Failed to send text"
+  "loki.quick_error": "Failed to send text",
+
+  "nav.llm_chat":   "LLM Chat",
+  "nav.llm_config": "LLM & MCP",
+
+  "llm_chat.checking":        "checking...",
+  "llm_chat.disabled":        "LLM disabled",
+  "llm_chat.online":          "online",
+  "llm_chat.unavailable":     "unavailable",
+  "llm_chat.disabled_msg":    "LLM is disabled. Enable it in",
+  "llm_chat.settings_link":   "Settings → LLM Bridge",
+  "llm_chat.thinking":        "Bjorn is thinking...",
+  "llm_chat.placeholder":     "Ask Bjorn anything about the network...",
+  "llm_chat.send":            "SEND",
+  "llm_chat.clear_history":   "Clear history",
+  "llm_chat.orch_log":        "Orch Log",
+  "llm_chat.orch_title":      "View LLM Orchestrator reasoning log",
+  "llm_chat.back_chat":       "← Back to chat",
+  "llm_chat.session_started": "Session started. Type a question or command.",
+  "llm_chat.history_cleared": "History cleared.",
+  "llm_chat.back_to_chat":    "Back to chat. Type a question or command.",
+  "llm_chat.loading_log":     "Loading LLM Orchestrator reasoning log…",
+  "llm_chat.no_log":          "No reasoning log yet. Enable llm_orchestrator_log_reasoning in config and run a cycle.",
+  "llm_chat.log_header":      "Orchestrator log",
+  "llm_chat.log_error":       "Error loading reasoning log",
+  "llm_chat.error":           "Error",
+  "llm_chat.net_error":       "Network error",
+
+  "llm_cfg.enable_bridge":      "Enable LLM Bridge",
+  "llm_cfg.epd_comments":       "LLM comments on EPD display",
+  "llm_cfg.backend":            "BACKEND PRIORITY",
+  "llm_cfg.laruche_discovery":  "Auto-discover LaRuche nodes via mDNS",
+  "llm_cfg.laruche_url":        "LARUCHE NODE URL (optional — overrides discovery)",
+  "llm_cfg.ollama_url":         "OLLAMA URL",
+  "llm_cfg.ollama_model":       "MODEL",
+  "llm_cfg.provider":           "PROVIDER",
+  "llm_cfg.api_model":          "MODEL",
+  "llm_cfg.api_key":            "API KEY",
+  "llm_cfg.api_key_placeholder":"Leave empty to keep current",
+  "llm_cfg.base_url":           "CUSTOM BASE URL (OpenRouter / proxy)",
+  "llm_cfg.timeout":            "TIMEOUT (s)",
+  "llm_cfg.max_tokens_chat":    "MAX TOKENS (chat)",
+  "llm_cfg.max_tokens_epd":     "MAX TOKENS (EPD comment)",
+  "llm_cfg.api_key_set":        "API key: set",
+  "llm_cfg.api_key_not_set":    "API key: not set",
+  "llm_cfg.save_llm":           "SAVE LLM CONFIG",
+  "llm_cfg.test_connection":    "TEST CONNECTION",
+  "llm_cfg.enable_mcp":         "Enable MCP Server",
+  "llm_cfg.transport":          "TRANSPORT",
+  "llm_cfg.mcp_port":           "PORT (HTTP SSE only)",
+  "llm_cfg.exposed_tools":      "EXPOSED TOOLS",
+  "llm_cfg.mcp_running":        "Server running on port",
+  "llm_cfg.mcp_stopped":        "Server not running.",
+  "llm_cfg.save_mcp":           "SAVE MCP CONFIG",
+  "llm_cfg.saved_llm":          "LLM config saved.",
+  "llm_cfg.saved_mcp":          "MCP config saved.",
+  "llm_cfg.mcp_enabled":        "MCP server enabled.",
+  "llm_cfg.mcp_disabled":       "MCP server disabled.",
+  "llm_cfg.testing":            "Testing…",
+  "llm_cfg.test_failed":        "Failed",
+  "llm_cfg.error":              "Error",
+  "llm_cfg.save_error":         "Save error"
 }