test(tools): add unit tests for error handling functions

* Implement tests for error functions like errRequiredField, errInvalidField, and errEntityNotFound.
* Ensure proper metadata is returned for various error scenarios.
* Validate error handling in CRM, Files, and other tools.
* Introduce tests for parsing stored file IDs and UUIDs.
* Enhance coverage for helper functions related to project resolution and session management.

internal/mcpserver/eventstore.go

@@ -0,0 +1,42 @@
+package mcpserver
+
+import (
+	"context"
+	"iter"
+
+	"github.com/modelcontextprotocol/go-sdk/mcp"
+)
+
+type cleanupEventStore struct {
+	base            mcp.EventStore
+	onSessionClosed func(string)
+}
+
+func newCleanupEventStore(base mcp.EventStore, onSessionClosed func(string)) mcp.EventStore {
+	return &cleanupEventStore{
+		base:            base,
+		onSessionClosed: onSessionClosed,
+	}
+}
+
+func (s *cleanupEventStore) Open(ctx context.Context, sessionID, streamID string) error {
+	return s.base.Open(ctx, sessionID, streamID)
+}
+
+func (s *cleanupEventStore) Append(ctx context.Context, sessionID, streamID string, data []byte) error {
+	return s.base.Append(ctx, sessionID, streamID, data)
+}
+
+func (s *cleanupEventStore) After(ctx context.Context, sessionID, streamID string, index int) iter.Seq2[[]byte, error] {
+	return s.base.After(ctx, sessionID, streamID, index)
+}
+
+func (s *cleanupEventStore) SessionClosed(ctx context.Context, sessionID string) error {
+	if err := s.base.SessionClosed(ctx, sessionID); err != nil {
+		return err
+	}
+	if s.onSessionClosed != nil {
+		s.onSessionClosed(sessionID)
+	}
+	return nil
+}