refactor: rename sisyphus_task to delegate_task

- Rename directories: sisyphus-task → delegate-task
- Rename types: SisyphusTaskArgs → DelegateTaskArgs, etc.
- Rename functions: createSisyphusTask → createDelegateTask
- Rename constants: SISYPHUS_TASK_* → DELEGATE_TASK_*
- Update tool name: sisyphus_task → delegate_task
- Update all prompts, docs, and tests

src/agents/prometheus-prompt.ts

@@ -291,8 +291,8 @@ Or should I just note down this single fix?"
 
 **Research First:**
 \`\`\`typescript
-sisyphus_task(agent="explore", prompt="Find all usages of [target] using lsp_find_references pattern...", background=true)
-sisyphus_task(agent="explore", prompt="Find test coverage for [affected code]...", background=true)
+delegate_task(agent="explore", prompt="Find all usages of [target] using lsp_find_references pattern...", background=true)
+delegate_task(agent="explore", prompt="Find test coverage for [affected code]...", background=true)
 \`\`\`
 
 **Interview Focus:**
@@ -315,9 +315,9 @@ sisyphus_task(agent="explore", prompt="Find test coverage for [affected code]...
 **Pre-Interview Research (MANDATORY):**
 \`\`\`typescript
 // Launch BEFORE asking user questions
-sisyphus_task(agent="explore", prompt="Find similar implementations in codebase...", background=true)
-sisyphus_task(agent="explore", prompt="Find project patterns for [feature type]...", background=true)
-sisyphus_task(agent="librarian", prompt="Find best practices for [technology]...", background=true)
+delegate_task(agent="explore", prompt="Find similar implementations in codebase...", background=true)
+delegate_task(agent="explore", prompt="Find project patterns for [feature type]...", background=true)
+delegate_task(agent="librarian", prompt="Find best practices for [technology]...", background=true)
 \`\`\`
 
 **Interview Focus** (AFTER research):
@@ -356,7 +356,7 @@ Based on your stack, I'd recommend NextAuth.js - it integrates well with Next.js
 
 Run this check:
 \`\`\`typescript
-sisyphus_task(agent="explore", prompt="Find test infrastructure: package.json test scripts, test config files (jest.config, vitest.config, pytest.ini, etc.), existing test files (*.test.*, *.spec.*, test_*). Report: 1) Does test infra exist? 2) What framework? 3) Example test file patterns.", background=true)
+delegate_task(agent="explore", prompt="Find test infrastructure: package.json test scripts, test config files (jest.config, vitest.config, pytest.ini, etc.), existing test files (*.test.*, *.spec.*, test_*). Report: 1) Does test infra exist? 2) What framework? 3) Example test file patterns.", background=true)
 \`\`\`
 
 #### Step 2: Ask the Test Question (MANDATORY)
@@ -445,13 +445,13 @@ Add to draft immediately:
 
 **Research First:**
 \`\`\`typescript
-sisyphus_task(agent="explore", prompt="Find current system architecture and patterns...", background=true)
-sisyphus_task(agent="librarian", prompt="Find architectural best practices for [domain]...", background=true)
+delegate_task(agent="explore", prompt="Find current system architecture and patterns...", background=true)
+delegate_task(agent="librarian", prompt="Find architectural best practices for [domain]...", background=true)
 \`\`\`
 
 **Oracle Consultation** (recommend when stakes are high):
 \`\`\`typescript
-sisyphus_task(agent="oracle", prompt="Architecture consultation needed: [context]...", background=false)
+delegate_task(agent="oracle", prompt="Architecture consultation needed: [context]...", background=false)
 \`\`\`
 
 **Interview Focus:**
@@ -468,9 +468,9 @@ sisyphus_task(agent="oracle", prompt="Architecture consultation needed: [context
 
 **Parallel Investigation:**
 \`\`\`typescript
-sisyphus_task(agent="explore", prompt="Find how X is currently handled...", background=true)
-sisyphus_task(agent="librarian", prompt="Find official docs for Y...", background=true)
-sisyphus_task(agent="librarian", prompt="Find OSS implementations of Z...", background=true)
+delegate_task(agent="explore", prompt="Find how X is currently handled...", background=true)
+delegate_task(agent="librarian", prompt="Find official docs for Y...", background=true)
+delegate_task(agent="librarian", prompt="Find OSS implementations of Z...", background=true)
 \`\`\`
 
 **Interview Focus:**
@@ -496,17 +496,17 @@ sisyphus_task(agent="librarian", prompt="Find OSS implementations of Z...", back
 
 **For Understanding Codebase:**
 \`\`\`typescript
-sisyphus_task(agent="explore", prompt="Find all files related to [topic]. Show patterns, conventions, and structure.", background=true)
+delegate_task(agent="explore", prompt="Find all files related to [topic]. Show patterns, conventions, and structure.", background=true)
 \`\`\`
 
 **For External Knowledge:**
 \`\`\`typescript
-sisyphus_task(agent="librarian", prompt="Find official documentation for [library]. Focus on [specific feature] and best practices.", background=true)
+delegate_task(agent="librarian", prompt="Find official documentation for [library]. Focus on [specific feature] and best practices.", background=true)
 \`\`\`
 
 **For Implementation Examples:**
 \`\`\`typescript
-sisyphus_task(agent="librarian", prompt="Find open source implementations of [feature]. Look for production-quality examples.", background=true)
+delegate_task(agent="librarian", prompt="Find open source implementations of [feature]. Look for production-quality examples.", background=true)
 \`\`\`
 
 ## Interview Mode Anti-Patterns
@@ -599,7 +599,7 @@ todoWrite([
 **BEFORE generating the plan**, summon Metis to catch what you might have missed:
 
 \`\`\`typescript
-sisyphus_task(
+delegate_task(
   agent="Metis (Plan Consultant)",
   prompt=\`Review this planning session before I generate the work plan:
 
@@ -750,7 +750,7 @@ If no, the plan is ready. Run \`/start-work\` to begin."
 \`\`\`typescript
 // After generating initial plan
 while (true) {
-  const result = sisyphus_task(
+  const result = delegate_task(
     agent="Momus (Plan Reviewer)",
     prompt=".sisyphus/plans/{name}.md",
     background=false