Address review feedback on multi-select issue fields

- Wrap the deleteIssueFieldValue mutation with WithGraphQLFeatures
  ("issue_fields", "repo_issue_fields") to match every sibling issue-field
  GraphQL op; without it the clear can silently no-op when gated.
- Reuse parseStringSlice for field_option_names (optionalIssueWriteFields)
  and multi_select_option_ids (set_issue_fields) instead of hand-rolling
  []string/[]any coercion in three places.
- Trim whitespace in matchOption so list_issues field_filters matches
  options consistently with issue_write (e.g. " Auth "). Adds a regression
  test.
- Trim two verbose comments per review.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: owenniblock

pkg/github/issues.go

@@ -297,21 +297,11 @@ func optionalIssueWriteFields(args map[string]any) ([]issueWriteFieldInput, erro
 		var fieldOptionNames []string
 		_, hasNamesKey := itemMap["field_option_names"]
 		if rawNames := itemMap["field_option_names"]; hasNamesKey && rawNames != nil {
-			switch v := rawNames.(type) {
-			case []string:
-				fieldOptionNames = v
-			case []any:
-				fieldOptionNames = make([]string, 0, len(v))
-				for _, item := range v {
-					s, ok := item.(string)
-					if !ok {
-						return nil, fmt.Errorf("field_option_names for field %q must be an array of strings", fieldName)
-					}
-					fieldOptionNames = append(fieldOptionNames, s)
-				}
-			default:
+			parsed, err := parseStringSlice(rawNames)
+			if err != nil {
 				return nil, fmt.Errorf("field_option_names for field %q must be an array of strings", fieldName)
 			}
+			fieldOptionNames = parsed
 		}
 
 		deleteField, _ := OptionalParam[bool](itemMap, "delete")
@@ -491,10 +481,8 @@ func resolveIssueRequestFieldValues(ctx context.Context, gqlClient *githubv4.Cli
 			// REST IssueField#build_value_attributes for multi_select expects an array of option names.
 			resolvedValue = resolvedNames
 		default:
-			// Raw value path. Reject it for multi_select so callers get a clear error
-			// instead of an opaque REST 422 — they should use field_option_names which
-			// validates options up front. Single_select keeps the existing pass-through
-			// behaviour for backwards compatibility (field_option_name is the validated path).
+			// multi_select must go through field_option_names (which validates options);
+			// reject a raw value here so callers get a clear error instead of a REST 422.
 			if strings.EqualFold(dataType, "multi_select") {
 				return nil, nil, fmt.Errorf("issue field %q is multi_select, use field_option_names to set its value", fieldInput.FieldName)
 			}
@@ -564,9 +552,6 @@ func fetchExistingIssueFieldValues(ctx context.Context, gqlClient *githubv4.Clie
 			value = string(node.SingleSelectValue.Value)
 		case "IssueFieldMultiSelectValue":
 			fieldIDStr = node.MultiSelectValue.Field.FullDatabaseIDStr()
-			// REST IssueField#build_value_attributes for multi_select expects an array
-			// of option names. Pass the selected option names through so the merged
-			// update round-trips faithfully.
 			names := make([]string, 0, len(node.MultiSelectValue.Options))
 			for _, opt := range node.MultiSelectValue.Options {
 				names = append(names, string(opt.Name))
@@ -2595,6 +2580,7 @@ func UpdateIssue(ctx context.Context, client *github.Client, gqlClient *githubv4
 		if err != nil {
 			return ghErrors.NewGitHubGraphQLErrorResponse(ctx, "failed to look up issue for field deletion", err), nil
 		}
+		ctxWithFeatures := ghcontext.WithGraphQLFeatures(ctx, "issue_fields", "repo_issue_fields")
 		for _, deletion := range fieldsToDelete {
 			var mutation struct {
 				DeleteIssueFieldValue struct {
@@ -2607,7 +2593,7 @@ func UpdateIssue(ctx context.Context, client *github.Client, gqlClient *githubv4
 				IssueID: issueID,
 				FieldID: deletion.NodeID,
 			}
-			if err := gqlClient.Mutate(ctx, &mutation, input, nil); err != nil {
+			if err := gqlClient.Mutate(ctxWithFeatures, &mutation, input, nil); err != nil {
 				return ghErrors.NewGitHubGraphQLErrorResponse(ctx, "failed to delete issue field value", err), nil
 			}
 		}
@@ -3351,7 +3337,7 @@ func resolveFieldFilters(rawFilters []rawFieldFilter, fields []IssueField) ([]Is
 // or an error listing the valid options.
 func matchOption(field IssueField, value string) (string, error) {
 	for _, o := range field.Options {
-		if strings.EqualFold(o.Name, value) {
+		if strings.EqualFold(strings.TrimSpace(o.Name), strings.TrimSpace(value)) {
 			return o.Name, nil
 		}
 	}

pkg/github/issues_granular.go

@@ -1093,26 +1093,15 @@ func GranularSetIssueFields(t translations.TranslationHelperFunc) inventory.Serv
 					valueCount++
 				}
 				if rawIDs, exists := fieldMap["multi_select_option_ids"]; exists && rawIDs != nil {
-					var optionIDs []githubv4.ID
-					switch v := rawIDs.(type) {
-					case []string:
-						optionIDs = make([]githubv4.ID, 0, len(v))
-						for _, s := range v {
-							optionIDs = append(optionIDs, githubv4.ID(s))
-						}
-					case []any:
-						optionIDs = make([]githubv4.ID, 0, len(v))
-						for _, item := range v {
-							s, ok := item.(string)
-							if !ok {
-								return utils.NewToolResultError("multi_select_option_ids must be an array of strings"), nil, nil
-							}
-							optionIDs = append(optionIDs, githubv4.ID(s))
-						}
-					default:
+					ids, err := parseStringSlice(rawIDs)
+					if err != nil {
 						return utils.NewToolResultError("multi_select_option_ids must be an array of strings"), nil, nil
 					}
-					if len(optionIDs) > 0 {
+					if len(ids) > 0 {
+						optionIDs := make([]githubv4.ID, 0, len(ids))
+						for _, s := range ids {
+							optionIDs = append(optionIDs, githubv4.ID(s))
+						}
 						input.MultiSelectOptionIDs = &optionIDs
 						valueCount++
 					}

pkg/github/issues_multiselect_test.go

@@ -115,6 +115,19 @@ func Test_resolveFieldFilters_MultiSelect(t *testing.T) {
 		assert.Nil(t, out[0].SingleSelectOptionValue)
 	})
 
+	t.Run("trims surrounding whitespace when matching options", func(t *testing.T) {
+		raw := []rawFieldFilter{{
+			Name:      "Components",
+			Values:    []string{"  auth  ", " Billing"},
+			HasValues: true,
+		}}
+		out, err := resolveFieldFilters(raw, fields)
+		require.NoError(t, err)
+		require.Len(t, out, 1)
+		require.NotNil(t, out[0].MultiSelectOptionValues)
+		assert.Equal(t, []githubv4.String{"Auth", "Billing"}, *out[0].MultiSelectOptionValues)
+	})
+
 	t.Run("rejects unknown option and lists valid ones", func(t *testing.T) {
 		raw := []rawFieldFilter{{
 			Name:      "Components",