Refactor SEO automation into unified CLI application

Major refactoring to create a clean, integrated CLI application:

### New Features:
- Unified CLI executable (./seo) with simple command structure
- All commands accept optional CSV file arguments
- Auto-detection of latest files when no arguments provided
- Simplified output directory structure (output/ instead of output/reports/)
- Cleaner export filename format (all_posts_YYYY-MM-DD.csv)

### Commands:
- export: Export all posts from WordPress sites
- analyze [csv]: Analyze posts with AI (optional CSV input)
- recategorize [csv]: Recategorize posts with AI
- seo_check: Check SEO quality
- categories: Manage categories across sites
- approve [files]: Review and approve recommendations
- full_pipeline: Run complete workflow
- analytics, gaps, opportunities, report, status

### Changes:
- Moved all scripts to scripts/ directory
- Created config.yaml for configuration
- Updated all scripts to use output/ directory
- Deprecated old seo-cli.py in favor of new ./seo
- Added AGENTS.md and CHANGELOG.md documentation
- Consolidated README.md with updated usage

### Technical:
- Added PyYAML dependency
- Removed hardcoded configuration values
- All scripts now properly integrated
- Better error handling and user feedback

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

guides/OUTPUT_GUIDE.md

@@ -0,0 +1,61 @@
+# Output Directory
+
+Generated analysis results and logs.
+
+## Directory Structure
+
+```
+output/
+├── results/              (Analysis results)
+│   ├── seo_optimization_report.md       (📍 PRIMARY DELIVERABLE)
+│   ├── posts_with_analytics.csv         (Enriched posts dataset)
+│   ├── posts_prioritized.csv            (All posts ranked 0-100)
+│   ├── keyword_opportunities.csv        (26 optimization opportunities)
+│   └── content_gaps.csv                 (New content ideas)
+│
+└── logs/                 (Analysis logs)
+    ├── import_log.txt
+    ├── opportunity_analysis_log.txt
+    └── content_gap_analysis_log.txt
+```
+
+## Primary Deliverable
+
+**`results/seo_optimization_report.md`**
+- Executive summary with key metrics
+- Top 20 posts ranked by optimization potential
+- AI-generated recommendations for each post
+- Keyword opportunities breakdown
+- Content gap analysis
+- 90-day phased action plan
+- Estimated traffic gains
+
+## Supporting Files
+
+**`results/posts_prioritized.csv`**
+- All 262 posts ranked by priority score (0-100)
+- Use this to see the full ranking and select which posts to optimize next
+
+**`results/keyword_opportunities.csv`**
+- The 26 posts identified at positions 11-30
+- Includes AI recommendations and estimated gains
+- Sort by opportunity_score to find quick wins
+
+**`results/posts_with_analytics.csv`**
+- Enriched dataset with all metrics merged
+- Use for custom analysis or future reference
+
+## Log Files
+
+**`logs/import_log.txt`**
+- Analytics integration report
+- URL matching success rate
+- Any unmatched URLs for manual review
+
+**`logs/opportunity_analysis_log.txt`**
+- Keyword opportunity analysis details
+- Posts processed and opportunities found
+
+**`logs/content_gap_analysis_log.txt`**
+- Content gap analysis results
+- New topics identified