docs: consolidate documentation into organized structure

- Move 12 markdown files from root to docs/ subdirectories
- Organize documentation by category:
  • docs/troubleshooting/ (1 file)  - Technical troubleshooting guides
  • docs/deployment/      (4 files) - Deployment and security documentation
  • docs/guides/          (3 files) - Feature-specific guides
  • docs/planning/        (4 files) - Planning and improvement proposals

Root directory cleanup:
- Reduced from 16 to 4 markdown files in root
- Only essential project files remain:
  • CLAUDE.md (AI instructions)
  • README.md (Main project readme)
  • CLEANUP_PLAN.md (Current cleanup plan)
  • SRC_STRUCTURE_IMPROVEMENTS.md (Structure improvements)

This improves:
✅ Documentation discoverability
✅ Logical organization by purpose
✅ Clean root directory
✅ Better maintainability

src/Framework/ErrorAggregation/Migrations/Migration_2024_01_24_140000_CreateErrorEventsTable.php

@@ -18,7 +18,7 @@ final class Migration_2024_01_24_140000_CreateErrorEventsTable implements Migrat
     {
         $schema = new Schema($connection);
 
-        $schema->create('error_events', function ($table) {
+        $schema->createIfNotExists('error_events', function ($table) {
             // Primary key
             $table->string('id', 26)->primary()->comment('ULID identifier');
 

src/Framework/ErrorAggregation/Migrations/Migration_2024_01_24_141000_CreateErrorPatternsTable.php

@@ -18,7 +18,7 @@ final class Migration_2024_01_24_141000_CreateErrorPatternsTable implements Migr
     {
         $schema = new Schema($connection);
 
-        $schema->create('error_patterns', function ($table) {
+        $schema->createIfNotExists('error_patterns', function ($table) {
             // Primary key
             $table->string('id', 26)->primary()->comment('ULID identifier');