feat(examples): mount the pi-ai adapter in the TUI demo composition

openai + anthropic routes register keyless beside the direct deepseek
adapter — the catalog stays browsable and requests fail actionably until a
key arrives — with per-request apiKeyEnv resolution, so a user's settings
section (proxy baseURL, extra routes) and .env keys are the only steps to
turn them on.

examples/tui-agent/cordis.yml

@@ -30,6 +30,20 @@
     thinking: enabled
     reasoningEffort: max
 
+# The pi-ai multi-provider twin beside the direct adapter: openai + anthropic
+# routes register keyless (the catalog stays browsable; a request needs a
+# key). Keys resolve per request through the apiKeyEnv references, and a
+# `llm-pi-ai:` settings section overrides per provider — proxy baseURL, added
+# routes — without a restart.
+- id: llm-pi-ai
+  name: '@deepseek-ai/dsh-llm-pi-ai'
+  config:
+    providers:
+      openai:
+        apiKeyEnv: OPENAI_API_KEY
+      anthropic:
+        apiKeyEnv: ANTHROPIC_API_KEY
+
 # Local executor for the app bundle's bash tool.
 # Managed child-process groups for the bash executor (spawn/kill/output plumbing).
 - id: subprocess