feat(config): add per-agent model overrides (#510)

Allow overriding specific agent models without changing the entire profile.
Add model_overrides key to config that takes precedence over profile lookup.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

get-shit-done/bin/gsd-tools.js

@@ -3620,6 +3620,14 @@ function cmdScaffold(cwd, type, options, raw) {
 
 function resolveModelInternal(cwd, agentType) {
   const config = loadConfig(cwd);
+
+  // Check per-agent override first
+  const override = config.model_overrides?.[agentType];
+  if (override) {
+    return override === 'opus' ? 'inherit' : override;
+  }
+
+  // Fall back to profile lookup
   const profile = config.model_profile || 'balanced';
   const agentModels = MODEL_PROFILES[agentType];
   if (!agentModels) return 'sonnet';

get-shit-done/references/model-profiles.md

@@ -42,11 +42,27 @@ Orchestrators resolve model before spawning:
 
 ```
 1. Read .planning/config.json
-2. Get model_profile (default: "balanced")
-3. Look up agent in table above
+2. Check model_overrides for agent-specific override
+3. If no override, look up agent in profile table
 4. Pass model parameter to Task call
 ```
 
+## Per-Agent Overrides
+
+Override specific agents without changing the entire profile:
+
+```json
+{
+  "model_profile": "balanced",
+  "model_overrides": {
+    "gsd-executor": "opus",
+    "gsd-planner": "haiku"
+  }
+}
+```
+
+Overrides take precedence over the profile. Valid values: `opus`, `sonnet`, `haiku`.
+
 ## Switching Profiles
 
 Runtime: `/gsd:set-profile <profile>`