fix(agents): pass categories and skills to Sisyphus/Atlas prompts

Sisyphus and Atlas prompts were missing delegation guide because
availableCategories and availableSkills were not being passed to
createSisyphusAgent() and createAtlasAgent() in utils.ts.

This caused buildCategorySkillsDelegationGuide() to return empty string,
resulting in agents not knowing when/how to delegate to explore, librarian,
or use category+skills based delegation.

src/agents/utils.ts

@@ -9,10 +9,11 @@ import { createMultimodalLookerAgent, MULTIMODAL_LOOKER_PROMPT_METADATA } from "
 import { createMetisAgent } from "./metis"
 import { createAtlasAgent } from "./atlas"
 import { createMomusAgent } from "./momus"
-import type { AvailableAgent } from "./dynamic-agent-prompt-builder"
+import type { AvailableAgent, AvailableCategory, AvailableSkill } from "./dynamic-agent-prompt-builder"
 import { deepMerge } from "../shared"
-import { DEFAULT_CATEGORIES } from "../tools/delegate-task/constants"
+import { DEFAULT_CATEGORIES, CATEGORY_DESCRIPTIONS } from "../tools/delegate-task/constants"
 import { resolveMultipleSkills } from "../features/opencode-skill-loader/skill-content"
+import { createBuiltinSkills } from "../features/builtin-skills"
 
 type AgentSource = AgentFactory | AgentConfig
 
@@ -149,6 +150,18 @@ export function createBuiltinAgents(
     ? { ...DEFAULT_CATEGORIES, ...categories }
     : DEFAULT_CATEGORIES
 
+  const availableCategories: AvailableCategory[] = Object.entries(mergedCategories).map(([name]) => ({
+    name,
+    description: CATEGORY_DESCRIPTIONS[name] ?? "General tasks",
+  }))
+
+  const builtinSkills = createBuiltinSkills()
+  const availableSkills: AvailableSkill[] = builtinSkills.map((skill) => ({
+    name: skill.name,
+    description: skill.description,
+    location: "plugin" as const,
+  }))
+
   for (const [name, source] of Object.entries(agentSources)) {
     const agentName = name as BuiltinAgentName
 
@@ -186,7 +199,13 @@ export function createBuiltinAgents(
     const sisyphusOverride = agentOverrides["Sisyphus"]
     const sisyphusModel = sisyphusOverride?.model ?? systemDefaultModel
 
-    let sisyphusConfig = createSisyphusAgent(sisyphusModel, availableAgents)
+    let sisyphusConfig = createSisyphusAgent(
+      sisyphusModel,
+      availableAgents,
+      undefined,
+      availableSkills,
+      availableCategories
+    )
 
     if (directory && sisyphusConfig.prompt) {
       const envContext = createEnvContext()
@@ -206,6 +225,8 @@ export function createBuiltinAgents(
      let orchestratorConfig = createAtlasAgent({
        model: orchestratorModel,
        availableAgents,
+       availableSkills,
+       userCategories: categories,
      })
 
     if (orchestratorOverride) {