Improved code by updating any interfaces

Change-Id: I9a2e630c37f3c427569f5bbd773978c2705dc08c
diff --git a/tools/metadata_test.go b/tools/metadata_test.go
index 04a067c..f1194d0 100644
--- a/tools/metadata_test.go
+++ b/tools/metadata_test.go
@@ -38,13 +38,13 @@
 	assert.Equal(t, false, schema["additionalProperties"])
 
 	// Verify properties exist
-	properties, ok := schema["properties"].(map[string]interface{})
+	properties, ok := schema["properties"].(map[string]any)
 	assert.True(t, ok)
 	assert.Contains(t, properties, "action")
 	assert.Contains(t, properties, "corpus")
 
 	// Verify action property details
-	action, ok := properties["action"].(map[string]interface{})
+	action, ok := properties["action"].(map[string]any)
 	assert.True(t, ok)
 	assert.Equal(t, "string", action["type"])
 	assert.Contains(t, action["description"], "Type of metadata operation")
@@ -61,7 +61,7 @@
 	assert.Contains(t, actionExamples, "statistics")
 
 	// Verify corpus property details
-	corpus, ok := properties["corpus"].(map[string]interface{})
+	corpus, ok := properties["corpus"].(map[string]any)
 	assert.True(t, ok)
 	assert.Equal(t, "string", corpus["type"])
 	assert.Contains(t, corpus["description"], "Virtual corpus query")
@@ -89,7 +89,7 @@
 	// Create request without action parameter
 	request := mcp.CallToolRequest{
 		Params: mcp.CallToolParams{
-			Arguments: map[string]interface{}{},
+			Arguments: map[string]any{},
 		},
 	}
 
@@ -103,7 +103,7 @@
 
 	request := mcp.CallToolRequest{
 		Params: mcp.CallToolParams{
-			Arguments: map[string]interface{}{
+			Arguments: map[string]any{
 				"action": "list",
 			},
 		},
@@ -120,7 +120,7 @@
 
 	request := mcp.CallToolRequest{
 		Params: mcp.CallToolParams{
-			Arguments: map[string]interface{}{
+			Arguments: map[string]any{
 				"action": "unknown",
 			},
 		},
@@ -138,7 +138,7 @@
 
 	request := mcp.CallToolRequest{
 		Params: mcp.CallToolParams{
-			Arguments: map[string]interface{}{
+			Arguments: map[string]any{
 				"action": "statistics",
 			},
 		},
@@ -160,19 +160,19 @@
 
 	tests := []struct {
 		name      string
-		arguments map[string]interface{}
+		arguments map[string]any
 		expectErr bool
 	}{
 		{
 			name: "list_action",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "list",
 			},
 			expectErr: true, // Will fail at authentication
 		},
 		{
 			name: "statistics_action",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 				"corpus": "test-corpus",
 			},
@@ -180,7 +180,7 @@
 		},
 		{
 			name: "statistics_with_empty_corpus",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 				"corpus": "",
 			},
@@ -276,7 +276,7 @@
 		Tokens:     100000,
 		Sentences:  5000,
 		Paragraphs: 1000,
-		Fields: map[string]interface{}{
+		Fields: map[string]any{
 			"genre":    "literature",
 			"language": "German",
 			"year":     2023,
@@ -310,27 +310,27 @@
 
 	tests := []struct {
 		name        string
-		arguments   map[string]interface{}
+		arguments   map[string]any
 		expectValid bool
 		errorMsg    string
 	}{
 		{
 			name: "valid_list_minimal",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "list",
 			},
 			expectValid: true,
 		},
 		{
 			name: "valid_statistics_minimal",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 			},
 			expectValid: true,
 		},
 		{
 			name: "valid_statistics_with_corpus",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 				"corpus": "test-corpus",
 			},
@@ -338,7 +338,7 @@
 		},
 		{
 			name: "valid_list_with_corpus_ignored",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "list",
 				"corpus": "test-corpus", // Should be ignored for list action
 			},
@@ -346,7 +346,7 @@
 		},
 		{
 			name: "missing_required_action",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"corpus": "test-corpus",
 			},
 			expectValid: false,
@@ -354,7 +354,7 @@
 		},
 		{
 			name: "invalid_action",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "invalid",
 			},
 			expectValid: false,
@@ -362,7 +362,7 @@
 		},
 		{
 			name: "empty_action",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "",
 			},
 			expectValid: false,
@@ -370,7 +370,7 @@
 		},
 		{
 			name: "invalid_corpus_format",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 				"corpus": "invalid@corpus#format",
 			},
@@ -379,7 +379,7 @@
 		},
 		{
 			name: "valid_corpus_with_boolean",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 				"corpus": "corpus1 & corpus2",
 			},
@@ -387,7 +387,7 @@
 		},
 		{
 			name: "valid_collection_query",
-			arguments: map[string]interface{}{
+			arguments: map[string]any{
 				"action": "statistics",
 				"corpus": "textClass = \"politics\" & pubDate in 2020",
 			},