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/Discovery/ValueObjects/InterfaceMapping.php

@@ -69,4 +69,28 @@ final readonly class InterfaceMapping
 
         return Byte::fromBytes($bytes);
     }
+
+    /**
+     * Serialize to array for cache storage
+     */
+    public function toArray(): array
+    {
+        return [
+            'interface' => $this->interface->getFullyQualified(),
+            'implementation' => $this->implementation->getFullyQualified(),
+            'file' => $this->file->toString(),
+        ];
+    }
+
+    /**
+     * Create from array for cache deserialization
+     */
+    public static function fromArray(array $data): self
+    {
+        return new self(
+            interface: ClassName::create($data['interface']),
+            implementation: ClassName::create($data['implementation']),
+            file: FilePath::create($data['file'])
+        );
+    }
 }