Implement CYA-WP-0008 llm-connect adapter integration.

Wire LLMConnectAdapter behind the existing LLMAdapter seam with config-driven
selection, graceful degradation, --offline mode, and bounded session context.
Add unit tests, integration docs, and update README/SCOPE/AGENTS.

docs/cya-config.example.toml

@@ -0,0 +1,9 @@
+# Example ~/.config/cya/config.toml — placeholders only; do not commit secrets.
+
+[llm]
+adapter = "connect"
+backend = "openrouter"
+model = "anthropic/claude-sonnet-4"
+temperature = 0.3
+max_tokens = 2000
+api_key_env = "OPENROUTER_API_KEY"