fix: expand override.category and explicit reasoningEffort priority (#1219) (#1235)

* fix: expand override.category and explicit reasoningEffort priority (#1219)

Two bugs fixed:

1. createBuiltinAgents(): override.category was never expanded into concrete
   config properties (model, variant, reasoningEffort, etc.). Added
   applyCategoryOverride() helper and applied it in the standard agent loop,
   Sisyphus path, and Atlas path.

2. Prometheus config-handler: reasoningEffort/textVerbosity/thinking from
   direct override now use explicit priority chains (direct > category)
   matching the existing variant pattern, instead of relying on spread
   ordering.

Priority order (highest to lowest):
  1. Direct override properties
  2. Override category properties
  3. Resolved variant from model fallback chain
  4. Factory base defaults

Closes #1219

* fix: use undefined check for thinking to allow explicit false

src/agents/utils.ts

@@ -120,6 +120,33 @@ export function createEnvContext(): string {
 </omo-env>`
 }
 
+/**
+ * Expands a category reference from an agent override into concrete config properties.
+ * Category properties are applied unconditionally (overwriting factory defaults),
+ * because the user's chosen category should take priority over factory base values.
+ * Direct override properties applied later via mergeAgentConfig() will supersede these.
+ */
+function applyCategoryOverride(
+  config: AgentConfig,
+  categoryName: string,
+  mergedCategories: Record<string, CategoryConfig>
+): AgentConfig {
+  const categoryConfig = mergedCategories[categoryName]
+  if (!categoryConfig) return config
+
+  const result = { ...config } as AgentConfig & Record<string, unknown>
+  if (categoryConfig.model) result.model = categoryConfig.model
+  if (categoryConfig.variant !== undefined) result.variant = categoryConfig.variant
+  if (categoryConfig.temperature !== undefined) result.temperature = categoryConfig.temperature
+  if (categoryConfig.reasoningEffort !== undefined) result.reasoningEffort = categoryConfig.reasoningEffort
+  if (categoryConfig.textVerbosity !== undefined) result.textVerbosity = categoryConfig.textVerbosity
+  if (categoryConfig.thinking !== undefined) result.thinking = categoryConfig.thinking
+  if (categoryConfig.top_p !== undefined) result.top_p = categoryConfig.top_p
+  if (categoryConfig.maxTokens !== undefined) result.maxTokens = categoryConfig.maxTokens
+
+  return result as AgentConfig
+}
+
 function mergeAgentConfig(
   base: AgentConfig,
   override: AgentOverrideConfig
@@ -210,18 +237,23 @@ export async function createBuiltinAgents(
 
     let config = buildAgent(source, model, mergedCategories, gitMasterConfig, browserProvider)
     
-    // Apply variant from override or resolved fallback chain
-    if (override?.variant) {
-      config = { ...config, variant: override.variant }
-    } else if (resolvedVariant) {
+    // Apply resolved variant from model fallback chain
+    if (resolvedVariant) {
       config = { ...config, variant: resolvedVariant }
     }
 
+    // Expand override.category into concrete properties (higher priority than factory/resolved)
+    const overrideCategory = (override as Record<string, unknown> | undefined)?.category as string | undefined
+    if (overrideCategory) {
+      config = applyCategoryOverride(config, overrideCategory, mergedCategories)
+    }
+
     if (agentName === "librarian" && directory && config.prompt) {
       const envContext = createEnvContext()
       config = { ...config, prompt: config.prompt + envContext }
     }
 
+    // Direct override properties take highest priority
     if (override) {
       config = mergeAgentConfig(config, override)
     }
@@ -261,12 +293,15 @@ export async function createBuiltinAgents(
         availableCategories
       )
       
-      if (sisyphusOverride?.variant) {
-        sisyphusConfig = { ...sisyphusConfig, variant: sisyphusOverride.variant }
-      } else if (sisyphusResolvedVariant) {
+      if (sisyphusResolvedVariant) {
         sisyphusConfig = { ...sisyphusConfig, variant: sisyphusResolvedVariant }
       }
 
+      const sisOverrideCategory = (sisyphusOverride as Record<string, unknown> | undefined)?.category as string | undefined
+      if (sisOverrideCategory) {
+        sisyphusConfig = applyCategoryOverride(sisyphusConfig, sisOverrideCategory, mergedCategories)
+      }
+
       if (directory && sisyphusConfig.prompt) {
         const envContext = createEnvContext()
         sisyphusConfig = { ...sisyphusConfig, prompt: sisyphusConfig.prompt + envContext }
@@ -302,12 +337,15 @@ export async function createBuiltinAgents(
         userCategories: categories,
       })
       
-      if (orchestratorOverride?.variant) {
-        orchestratorConfig = { ...orchestratorConfig, variant: orchestratorOverride.variant }
-      } else if (atlasResolvedVariant) {
+      if (atlasResolvedVariant) {
         orchestratorConfig = { ...orchestratorConfig, variant: atlasResolvedVariant }
       }
 
+      const atlasOverrideCategory = (orchestratorOverride as Record<string, unknown> | undefined)?.category as string | undefined
+      if (atlasOverrideCategory) {
+        orchestratorConfig = applyCategoryOverride(orchestratorConfig, atlasOverrideCategory, mergedCategories)
+      }
+
       if (orchestratorOverride) {
         orchestratorConfig = mergeAgentConfig(orchestratorConfig, orchestratorOverride)
       }