fix(backend): Fix MCP module compilation errors by using correct exception classes

Replaced non-existent ColaFlow.Shared.Kernel.Exceptions namespace references
with ColaFlow.Modules.Mcp.Domain.Exceptions in 5 files:

Changes:
- McpToolRegistry.cs: Use McpInvalidParamsException and McpNotFoundException
- AddCommentTool.cs: Use McpInvalidParamsException and McpNotFoundException
- CreateIssueTool.cs: Use McpInvalidParamsException, McpNotFoundException, and ProjectId.From()
- UpdateStatusTool.cs: Use McpNotFoundException
- ToolParameterParser.cs: Use McpInvalidParamsException for all validation errors

All BadRequestException -> McpInvalidParamsException
All NotFoundException -> McpNotFoundException

Also fixed CreateIssueTool to convert Guid to ProjectId value object.

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

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

colaflow-api/src/Modules/Mcp/ColaFlow.Modules.Mcp.Application/Services/IMcpToolRegistry.cs

@@ -0,0 +1,32 @@
+using ColaFlow.Modules.Mcp.Contracts.Tools;
+
+namespace ColaFlow.Modules.Mcp.Application.Services;
+
+/// <summary>
+/// Registry interface for MCP Tools
+/// Manages tool discovery and dispatching
+/// </summary>
+public interface IMcpToolRegistry
+{
+    /// <summary>
+    /// Get all registered tools
+    /// </summary>
+    IEnumerable<IMcpTool> GetAllTools();
+
+    /// <summary>
+    /// Get tool by name
+    /// </summary>
+    IMcpTool? GetTool(string toolName);
+
+    /// <summary>
+    /// Check if tool exists
+    /// </summary>
+    bool HasTool(string toolName);
+
+    /// <summary>
+    /// Execute a tool by name
+    /// </summary>
+    Task<McpToolResult> ExecuteToolAsync(
+        McpToolCall toolCall,
+        CancellationToken cancellationToken = default);
+}