docs: consolidate repository guides and preserve audit history

docs/ai/providers.md

@@ -1,66 +1,5 @@
-# AI Providers
+# AI providers and routing
 
-## Purpose
+`AI_PROVIDER` selects the structured CV provider: `ollama` (default/local), `gemini`, or `groq`. `AI_ROUTING_MODE` is `local_only`, `local_first`, or `external_only`; external processing also requires the administrator gate, an allowed task, and the user's applicable opt-in/entitlement. Job summarisation remains local in the sidecar.
 
-Support multiple AI providers.
-
----
-
-# Current/Future Providers
-
-Possible:
-
-- OpenAI.
-- Anthropic.
-- Google Gemini.
-- Groq.
-- Ollama.
-- Other compatible APIs.
-
----
-
-# Provider Architecture
-
-Use abstraction:
-
-AI Provider Interface
-
-↓
-
-Provider Implementation
-
-↓
-
-Model
-
----
-
-# Requirements
-
-Users should eventually be able to:
-
-- Select provider.
-- Select model.
-- Configure API keys.
-
----
-
-# Admin Controls
-
-Admins should control:
-
-- Available providers.
-- Allowed models.
-- Usage limits.
-
----
-
-# SaaS Consideration
-
-Different plans may have:
-
-Free models.
-
-Premium models.
-
-BYO-key support.
+Ollama uses `OLLAMA_BASE_URL` and `OLLAMA_MODEL`. Gemini and Groq use their model, base URL, and API-key variables. Keep provider keys in the environment only. If a provider/model is unavailable, show a retriable/unavailable state rather than silently selecting an unevaluated model.