feat: implement modular capability system with automatic discovery

- Move release management to capabilities/release-management/ with complete Makefile
- Create automatic capability discovery system in scripts/capability_discovery.mk
- Add capability-manager subagent for managing modular architecture
- Implement target delegation system enabling capability-name-target patterns
- Create Makefiles for markitect-content, markitect-utils, and issue-facade capabilities
- Remove legacy release management code and documentation from main project
- Update main Makefile to use capability discovery and delegation
- Add comprehensive capability status, help, and management targets

The capability system provides:
- Automatic discovery of capabilities with Makefiles
- Clean target delegation without conflicts
- Modular architecture following established patterns
- Comprehensive help and status reporting
- Zero-conflict capability integration

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

pyproject.toml

@@ -8,7 +8,16 @@ dynamic = ["version"]
 description = "Advanced Markdown engine for structured content"
 readme = "README.md"
 requires-python = ">=3.8"
-dependencies = ["markdown-it-py", "PyYAML", "click>=8.0.0", "tabulate>=0.9.0", "jsonpath-ng>=1.5.0", "aiohttp>=3.8.0", "toml"]
+dependencies = [
+    "markdown-it-py",
+    "PyYAML",
+    "click>=8.0.0",
+    "tabulate>=0.9.0",
+    "jsonpath-ng>=1.5.0",
+    "aiohttp>=3.8.0",
+    "toml",
+    "release-management @ file:./capabilities/release-management"
+]
 
 [project.optional-dependencies]
 capabilities = [