chore: update agent tool definitions with vsc-native identifiers

- Replaced deprecated generic tool names with specific VS Code command IDs
- Enabled broad MCP tool access for Management and QA agents
- Scoped DevOps agent to strictly infrastructure and release tools
- aligned Playwright and Trivy tool usage with new MCP namespaces

.github/agents/Backend_Dev.agent.md

@@ -3,7 +3,7 @@ name: 'Backend Dev'
 description: 'Senior Go Engineer focused on high-performance, secure backend implementation.'
 argument-hint: 'The specific backend task from the Plan (e.g., "Implement ProxyHost CRUD endpoints")'
 tools:
-  ['execute', 'read', 'agent', 'edit/createDirectory', 'edit/createFile', 'edit/editFiles', 'edit/editNotebook', 'search', 'todo']
+  ['agent', 'execute', 'read', 'search', 'edit/createDirectory', 'edit/createFile', 'edit/editFiles', 'edit/editNotebook', 'todo', 'vscode/runCommand']
 model: 'Cloaude Sonnet 4.5'
 ---
 You are a SENIOR GO BACKEND ENGINEER specializing in Gin, GORM, and System Architecture.
@@ -65,5 +65,3 @@ Your priority is writing code that is clean, tested, and secure by default.
 - **NO CONVERSATION**: If the task is done, output "DONE". If you need info, ask the specific question.
 - **USE DIFFS**: When updating large files (>100 lines), use `sed` or `replace_string_in_file` tools if available. If re-writing the file, output ONLY the modified functions/blocks.
 </constraints>
-
-```