refactor(prompts): enrich explore/librarian delegation examples with structured context handoff

Expand prompt structure comment to 4-field format (CONTEXT/GOAL/DOWNSTREAM/REQUEST).
Update all explore/librarian task() examples across Sisyphus, Hephaestus,
Prometheus interview-mode, and both ultrawork variants with richer context
including downstream usage, scope limits, and return format expectations.

src/hooks/keyword-detector/ultrawork/default.ts

@@ -44,9 +44,9 @@ export const ULTRAWORK_DEFAULT_MESSAGE = `<ultrawork-mode>
 
 **WHEN IN DOUBT:**
 \`\`\`
-task(subagent_type="explore", load_skills=[], prompt="Find [X] patterns in codebase", run_in_background=true)
-task(subagent_type="librarian", load_skills=[], prompt="Find docs/examples for [Y]", run_in_background=true)
-task(subagent_type="oracle", load_skills=[], prompt="Review my approach: [describe plan]", run_in_background=false)
+task(subagent_type="explore", load_skills=[], prompt="I'm implementing [TASK DESCRIPTION] and need to understand [SPECIFIC KNOWLEDGE GAP]. Find [X] patterns in the codebase — show file paths, implementation approach, and conventions used. I'll use this to [HOW RESULTS WILL BE USED]. Focus on src/ directories, skip test files unless test patterns are specifically needed. Return concrete file paths with brief descriptions of what each file does.", run_in_background=true)
+task(subagent_type="librarian", load_skills=[], prompt="I'm working with [LIBRARY/TECHNOLOGY] and need [SPECIFIC INFORMATION]. Find official documentation and production-quality examples for [Y] — specifically: API reference, configuration options, recommended patterns, and common pitfalls. Skip beginner tutorials. I'll use this to [DECISION THIS WILL INFORM].", run_in_background=true)
+task(subagent_type="oracle", load_skills=[], prompt="I need architectural review of my approach to [TASK]. Here's my plan: [DESCRIBE PLAN WITH SPECIFIC FILES AND CHANGES]. My concerns are: [LIST SPECIFIC UNCERTAINTIES]. Please evaluate: correctness of approach, potential issues I'm missing, and whether a better alternative exists.", run_in_background=false)
 \`\`\`
 
 **ONLY AFTER YOU HAVE:**

src/hooks/keyword-detector/ultrawork/gpt5.2.ts

@@ -97,8 +97,8 @@ Use these when they provide clear value based on the decision framework above:
 **ALWAYS run both tracks in parallel:**
 \`\`\`
 // Fire background agents for deep exploration
-task(subagent_type="explore", load_skills=[], prompt="Find X patterns...", run_in_background=true)
-task(subagent_type="librarian", load_skills=[], prompt="Find docs for Y...", run_in_background=true)
+task(subagent_type="explore", load_skills=[], prompt="I'm implementing [TASK] and need to understand [KNOWLEDGE GAP]. Find [X] patterns in the codebase — file paths, implementation approach, conventions used, and how modules connect. I'll use this to [DOWNSTREAM DECISION]. Focus on production code in src/. Return file paths with brief descriptions.", run_in_background=true)
+task(subagent_type="librarian", load_skills=[], prompt="I'm working with [TECHNOLOGY] and need [SPECIFIC INFO]. Find official docs and production examples for [Y] — API reference, configuration, recommended patterns, and pitfalls. Skip tutorials. I'll use this to [DECISION THIS INFORMS].", run_in_background=true)
 
 // WHILE THEY RUN - use direct tools for immediate context
 grep(pattern="relevant_pattern", path="src/")