Refactor agent documentation and remove obsolete files

- Deleted `docs-agent.md`, `feature-agent.md`, `instructions-agent.md`, `test-agent.md`, and `Perf.chatmode.md` as they are no longer needed.
- Updated `implementation-planner.agent.md` to correct the name format.
- Added new `docs-agent.md`, `feature-agent.md`, `instructions-agent.md`, `test-agent.md`, and `perf.agent.md` with comprehensive guidelines for each agent's responsibilities and workflows.

Author: TyKonKet

.github/agents/docs-agent.md .github/agents/docs.agent.md.github/agents/docs-agent.md renamed to .github/agents/docs.agent.md

@@ -1,5 +1,5 @@
 ---
-name: implementation-planner
+name: implementation-planner-agent
 description: Creates detailed implementation plans and technical specifications in markdown format
 tools: ["read", "search", "edit"]
 ---

.github/agents/feature-agent.md .github/agents/feature.agent.md.github/agents/feature-agent.md renamed to .github/agents/feature.agent.md

@@ -1,6 +1,6 @@
 ---
 description: 'Performance optimization and benchmarking assistant for BarcodeGenerator library.'
-tools: ['codebase', 'usages', 'vscodeAPI', 'problems', 'changes', 'testFailure', 'openSimpleBrowser', 'fetch', 'findTestFiles', 'searchResults', 'githubRepo', 'extensions', 'todos', 'runTests', 'editFiles', 'runNotebooks', 'search', 'new', 'runCommands', 'runTasks', 'github', 'microsoft-docs', 'markitdown', 'sequentialthinking', 'copilotCodingAgent', 'activePullRequest', 'openPullRequest']
+tools: ['edit', 'runNotebooks', 'search', 'new', 'runCommands', 'runTasks', 'memory/*', 'microsoft-docs/*', 'sequentialthinking/*', 'usages', 'vscodeAPI', 'problems', 'changes', 'testFailure', 'openSimpleBrowser', 'fetch', 'githubRepo', 'extensions', 'todos', 'runSubagent', 'runTests']
 ---
 
 You are a performance optimization specialist focused on the BarcodeGenerator .NET library. Your primary goal is to help identify, analyze, and optimize performance bottlenecks while maintaining code quality and correctness.