Fix #10: Restructure plugin directories to ensure proper command isolation

- Create separate directories for each plugin (requirements-driven-workflow/, bmad-agile-workflow/, development-essentials/, advanced-ai-agents/)
- Update marketplace.json to use isolated source paths for each plugin
- Remove shared commands/ and agents/ directories that caused command leakage
- Each plugin now only shows its intended commands:
  - requirements-driven-workflow: 1 command (requirements-pilot)
  - bmad-agile-workflow: 1 command (bmad-pilot)
  - development-essentials: 10 commands (code, debug, test, etc.)
  - advanced-ai-agents: 0 commands (agents only)

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

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

bmad-agile-workflow/.claude-plugin/plugin.json

@@ -0,0 +1,37 @@
+{
+  "name": "bmad-agile-workflow",
+  "source": "./",
+  "description": "Full BMAD agile workflow with role-based agents (PO, Architect, SM, Dev, QA) and interactive approval gates",
+  "version": "1.0.0",
+  "author": {
+    "name": "Claude Code Dev Workflows",
+    "url": "https://github.com/yourusername/myclaude"
+  },
+  "homepage": "https://github.com/yourusername/myclaude",
+  "repository": "https://github.com/yourusername/myclaude",
+  "license": "MIT",
+  "keywords": [
+    "bmad",
+    "agile",
+    "scrum",
+    "product-owner",
+    "architect",
+    "developer",
+    "qa",
+    "workflow-orchestration"
+  ],
+  "category": "workflows",
+  "strict": false,
+  "commands": [
+    "./commands/bmad-pilot.md"
+  ],
+  "agents": [
+    "./agents/bmad-po.md",
+    "./agents/bmad-architect.md",
+    "./agents/bmad-sm.md",
+    "./agents/bmad-dev.md",
+    "./agents/bmad-qa.md",
+    "./agents/bmad-orchestrator.md",
+    "./agents/bmad-review.md"
+  ]
+}