Initial commit: Agentic OS troubleshooting platform

Self-hosted, Docker-based agentic troubleshooting platform: FastAPI backend +
LangGraph agent, Next.js UI, tiered LLM routing (local Ollama -> Gemini ->
DeepSeek -> OpenRouter), MCP server manager, encrypted device credentials,
RBAC, audit log, project-memory + Obsidian integrations, and editable
troubleshooting decision rules tuned for the GeneseasX vessel stack.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/tests/test_model_routing.py

@@ -0,0 +1,67 @@
+"""Tests for tiered model routing."""
+from __future__ import annotations
+
+import os
+
+os.environ.setdefault("SECRET_KEY", "test-secret-key-for-unit-tests-only")
+
+from app.services.model_config import (  # noqa: E402
+    LlmRoutingConfig,
+    resolve_tier_model,
+    resolve_tier_models,
+)
+from app.services.model_router import plan_reasoning_tiers  # noqa: E402
+
+
+def test_resolve_tier_models_provider_order(monkeypatch):
+    monkeypatch.setenv("GEMINI_API_KEY", "test-gemini")
+    monkeypatch.setenv("DEEPSEEK_API_KEY", "test-deepseek")
+    monkeypatch.setenv("OPENROUTER_API_KEY", "test-openrouter")
+
+    from app.config import get_settings
+
+    get_settings.cache_clear()
+
+    cfg = LlmRoutingConfig(
+        cloud_provider_order=["gemini", "deepseek", "openrouter"],
+    )
+    models = resolve_tier_models(cfg, "economy")
+    backends = [m.backend for m in models]
+    assert backends == ["gemini", "deepseek", "openrouter"]
+
+    get_settings.cache_clear()
+
+
+def test_resolve_tier_model_returns_first_provider(monkeypatch):
+    monkeypatch.setenv("GEMINI_API_KEY", "test-gemini")
+    monkeypatch.setenv("DEEPSEEK_API_KEY", "test-deepseek")
+
+    from app.config import get_settings
+
+    get_settings.cache_clear()
+
+    cfg = LlmRoutingConfig(cloud_provider_order=["gemini", "deepseek", "openrouter"])
+    entry = resolve_tier_model(cfg, "economy")
+    assert entry is not None
+    assert entry.backend == "gemini"
+
+    get_settings.cache_clear()
+
+
+def test_plan_reasoning_local_first():
+    tiers, reason = plan_reasoning_tiers(
+        {"severity": "low", "needs_cloud_reasoning": False, "recommended_tier": "local"},
+        [],
+        cfg=LlmRoutingConfig(),
+    )
+    assert tiers == ["local"]
+    assert "local" in reason.lower()
+
+
+def test_plan_reasoning_escalates_critical():
+    tiers, _ = plan_reasoning_tiers(
+        {"severity": "critical", "needs_cloud_reasoning": True, "recommended_tier": "premium"},
+        [{"ok": False}, {"ok": False}],
+        cfg=LlmRoutingConfig(),
+    )
+    assert tiers == ["local", "economy", "premium"]