fix(config): add resolve_model_ids to VALID_CONFIG_KEYS; accept workflow._auto_chain_active via RUNTIME_STATE_KEYS

Fixes #3162

`resolve_model_ids` is a documented top-level config key (CONFIGURATION.md)
read by core.cjs and session-runner.ts, but was missing from the CJS and SDK
VALID_CONFIG_KEYS allowlists — causing config-set to reject it with
"Unknown config key".

`workflow._auto_chain_active` is internal runtime state intentionally excluded
from VALID_CONFIG_KEYS by #2530, but plan-phase, execute-phase, discuss-phase,
transition, and new-project workflows all write it via `config-set`. Without
a valid write path these calls emit spurious errors (silenced with `|| true`
but noisy in logs). A new RUNTIME_STATE_KEYS set in config-schema.cjs holds
keys that isValidConfigKey() accepts without exposing them as user-settable
options — preserving the #2530 intent while fixing the runtime error.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

sdk/src/query/config-schema.ts

@@ -71,6 +71,8 @@ export const VALID_CONFIG_KEYS: ReadonlySet<string> = new Set([
   'claude_md_assembly.mode',
   // #2517 — runtime-aware model profiles
   'runtime',
+  // #3162 — documented top-level key: controls model ID resolution for non-Claude runtimes
+  'resolve_model_ids',
 ]);
 
 /**