Align tool-call parsing across Go/JS and pass quality gates

internal/util/toolcalls_parse_item.go

@@ -0,0 +1,88 @@
+package util
+
+import "strings"
+
+func isLikelyJSONToolPayloadCandidate(candidate string) bool {
+	trimmed := strings.TrimSpace(candidate)
+	if trimmed == "" {
+		return false
+	}
+	if !(strings.HasPrefix(trimmed, "{") || strings.HasPrefix(trimmed, "[")) {
+		return false
+	}
+	lower := strings.ToLower(trimmed)
+	return strings.Contains(lower, "tool_calls") ||
+		strings.Contains(lower, "\"function\"") ||
+		strings.Contains(lower, "functioncall") ||
+		strings.Contains(lower, "\"tool_use\"")
+}
+
+func parseToolCallList(v any) []ParsedToolCall {
+	items, ok := v.([]any)
+	if !ok {
+		return nil
+	}
+	out := make([]ParsedToolCall, 0, len(items))
+	for _, item := range items {
+		m, ok := item.(map[string]any)
+		if !ok {
+			continue
+		}
+		if tc, ok := parseToolCallItem(m); ok {
+			out = append(out, tc)
+		}
+	}
+	if len(out) == 0 {
+		return nil
+	}
+	return out
+}
+
+func parseToolCallItem(m map[string]any) (ParsedToolCall, bool) {
+	name, _ := m["name"].(string)
+	inputRaw, hasInput := m["input"]
+	if fnCall, ok := m["functionCall"].(map[string]any); ok {
+		if name == "" {
+			name, _ = fnCall["name"].(string)
+		}
+		if !hasInput {
+			if v, ok := fnCall["args"]; ok {
+				inputRaw = v
+				hasInput = true
+			}
+		}
+		if !hasInput {
+			if v, ok := fnCall["arguments"]; ok {
+				inputRaw = v
+				hasInput = true
+			}
+		}
+	}
+	if fn, ok := m["function"].(map[string]any); ok {
+		if name == "" {
+			name, _ = fn["name"].(string)
+		}
+		if !hasInput {
+			if v, ok := fn["arguments"]; ok {
+				inputRaw = v
+				hasInput = true
+			}
+		}
+	}
+	if !hasInput {
+		for _, key := range []string{"arguments", "args", "parameters", "params"} {
+			if v, ok := m[key]; ok {
+				inputRaw = v
+				hasInput = true
+				break
+			}
+		}
+	}
+	if strings.TrimSpace(name) == "" {
+		return ParsedToolCall{}, false
+	}
+	return ParsedToolCall{
+		Name:  strings.TrimSpace(name),
+		Input: parseToolCallInput(inputRaw),
+	}, true
+}