fix(runtime): unify claude thinking config resolution

internal/util/claude_thinking.go

@@ -0,0 +1,46 @@
+package util
+
+import (
+	"github.com/tidwall/gjson"
+	"github.com/tidwall/sjson"
+)
+
+// ApplyClaudeThinkingConfig applies thinking configuration to a Claude API request payload.
+// It sets the thinking.type to "enabled" and thinking.budget_tokens to the specified budget.
+// If budget is nil or the payload already has thinking config, it returns the payload unchanged.
+func ApplyClaudeThinkingConfig(body []byte, budget *int) []byte {
+	if budget == nil {
+		return body
+	}
+	if gjson.GetBytes(body, "thinking").Exists() {
+		return body
+	}
+	if *budget <= 0 {
+		return body
+	}
+	updated := body
+	updated, _ = sjson.SetBytes(updated, "thinking.type", "enabled")
+	updated, _ = sjson.SetBytes(updated, "thinking.budget_tokens", *budget)
+	return updated
+}
+
+// ResolveClaudeThinkingConfig resolves thinking configuration from metadata for Claude models.
+// It uses the unified ResolveThinkingConfigFromMetadata and normalizes the budget.
+// Returns the normalized budget (nil if thinking should not be enabled) and whether it matched.
+func ResolveClaudeThinkingConfig(modelName string, metadata map[string]any) (*int, bool) {
+	budget, include, matched := ResolveThinkingConfigFromMetadata(modelName, metadata)
+	if !matched {
+		return nil, false
+	}
+	if include != nil && !*include {
+		return nil, true
+	}
+	if budget == nil {
+		return nil, true
+	}
+	normalized := NormalizeThinkingBudget(modelName, *budget)
+	if normalized <= 0 {
+		return nil, true
+	}
+	return &normalized, true
+}