Add progressive disclosure formatting guidelines to daily-performance-summary workflow

.github/workflows/daily-performance-summary.md

@@ -722,6 +722,55 @@ Before creating the new discussion, find and close previous daily performance di
 2. Close each found discussion with reason "OUTDATED"
 3. Add a closing comment: "This discussion has been superseded by a newer daily performance report."
 
+## Phase 5.5: Report Formatting Guidelines
+
+**CRITICAL**: Follow these formatting guidelines to create well-structured, readable reports:
+
+### 1. Header Levels
+**Use h3 (###) or lower for all headers in your report to maintain proper document hierarchy.**
+
+The discussion title serves as h1, so all content headers should start at h3:
+- Use `###` for main sections (e.g., "### Performance Overview", "### Key Metrics")
+- Use `####` for subsections (e.g., "#### Pull Requests", "#### Issues")
+- Never use `##` (h2) or `#` (h1) in the report body
+
+### 2. Progressive Disclosure
+**Wrap long sections in `<details><summary><b>Section Name</b></summary>` tags to improve readability and reduce scrolling.**
+
+Use collapsible sections for:
+- Detailed benchmark results and performance data
+- Full performance metrics tables
+- Verbose statistics and historical comparisons
+- Technical implementation details
+
+Example:
+```markdown
+<details>
+<summary><b>Detailed Benchmark Results</b></summary>
+
+[Long performance data...]
+
+</details>
+```
+
+### 3. Report Structure Pattern
+
+Your report should follow this structure for optimal readability:
+
+1. **Performance Overview** (always visible): Brief executive summary highlighting overall project health, key achievements, and critical issues
+2. **Key Highlights** (always visible): Most important metrics and trends that stakeholders need to see immediately
+3. **Critical Performance Issues** (always visible): Any problems that require immediate attention with severity indicators
+4. **Detailed Benchmark Results** (in `<details>` tags): Comprehensive performance data, metrics tables, and historical comparisons
+5. **Optimization Recommendations** (always visible): Actionable insights and suggested improvements
+
+### Design Principles
+
+Create reports that:
+- **Build trust through clarity**: Most important info (overview, critical issues, recommendations) immediately visible
+- **Exceed expectations**: Add helpful context, trends, comparisons to give stakeholders the full picture
+- **Create delight**: Use progressive disclosure to reduce overwhelm while keeping details accessible
+- **Maintain consistency**: Follow the same patterns as other reporting workflows in this repository
+
 ## Phase 6: Create Discussion Report
 
 Create a new discussion with the comprehensive performance report.
@@ -733,35 +782,46 @@ Create a new discussion with the comprehensive performance report.
 **Body**:
 
 ```markdown
-Brief 2-3 paragraph executive summary highlighting:
-- Overall project health and activity levels
-- Key achievements (PRs merged, issues resolved)
-- Areas needing attention
+### Performance Overview
 
-<details>
-<summary><b>📊 Full Performance Report</b></summary>
+[Brief 2-3 paragraph executive summary highlighting overall project health and activity levels]
+
+### Key Highlights
+
+- ✅ **[NUMBER]** PRs merged in the last 90 days
+- 📊 **[NUMBER]** issues resolved  
+- 💬 **[NUMBER]** discussions answered
+- ⏱️ Average merge time: **[HOURS]** hours
+- 👥 **[NUMBER]** unique contributors
 
-## 📈 Activity Overview
+### 🚨 Critical Performance Issues
+
+[List any critical issues that require immediate attention. If none, state "No critical performance issues detected."]
+
+### 📈 Activity Overview
 
 ![Activity Overview](URL_FROM_UPLOAD_ASSET_CHART_1)
 
-[Brief analysis of activity distribution across PRs, issues, and discussions]
+[Brief 2-3 sentence analysis of activity distribution across PRs, issues, and discussions]
+
+<details>
+<summary><b>📊 Detailed Benchmark Results</b></summary>
 
-## 🎯 Resolution Metrics
+#### 🎯 Resolution Metrics
 
 ![Resolution Metrics](URL_FROM_UPLOAD_ASSET_CHART_2)
 
 [Analysis of PR merge rates and issue resolution rates]
 
-## ⚡ Velocity Metrics
+#### ⚡ Velocity Metrics
 
 ![Velocity Metrics](URL_FROM_UPLOAD_ASSET_CHART_3)
 
 [Analysis of response times, contributor activity, and discussion engagement]
 
-## 📊 Key Performance Indicators
+#### 📊 Complete Performance Data
 
-### Pull Requests
+##### Pull Requests
 | Metric | Value |
 |--------|-------|
 | Total PRs | [NUMBER] |
@@ -770,29 +830,33 @@ Brief 2-3 paragraph executive summary highlighting:
 | Avg Merge Time | [HOURS] hours |
 | Unique Contributors | [NUMBER] |
 
-### Issues
+##### Issues
 | Metric | Value |
 |--------|-------|
 | Total Issues | [NUMBER] |
 | Closed | [NUMBER] |
 | Open | [NUMBER] |
 | Avg Resolution Time | [HOURS] hours |
 
-### Discussions
+##### Discussions
 | Metric | Value |
 |--------|-------|
 | Total Discussions | [NUMBER] |
 | Answered | [NUMBER] |
 | Answer Rate | [PERCENT]% |
 
-## 💡 Insights & Recommendations
+#### 📈 Historical Comparisons
 
-1. [Key insight based on the data]
-2. [Recommendation for improvement]
-3. [Action item if needed]
+[Compare with previous periods if historical data is available]
 
 </details>
 
+### 💡 Optimization Recommendations
+
+1. [Actionable recommendation based on the data]
+2. [Specific suggestion for improvement]
+3. [Priority action item if needed]
+
 ---
 *Report generated automatically by the Daily Performance Summary workflow*
 *Data source: ${{ github.repository }} - Last 90 days*