Refactor: split prompt definition from execution settings and migrate run contracts to prompt_* + execution_target

internal/llm/openai_compatible_client.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"os"
 	"net/http"
 	"net/url"
 	"strings"
@@ -25,7 +26,6 @@ var (
 
 type OpenAICompatibleConfig struct {
 	BaseURL    string
-	APIKey     string
 	Model      string
 	Timeout    time.Duration
 	HTTPClient *http.Client
@@ -33,7 +33,6 @@ type OpenAICompatibleConfig struct {
 
 type OpenAICompatibleClient struct {
 	baseURL      string
-	apiKey       string
 	defaultModel string
 	timeout      time.Duration
 	httpClient   *http.Client
@@ -64,7 +63,6 @@ func NewOpenAICompatibleClient(cfg OpenAICompatibleConfig) (*OpenAICompatibleCli
 
 	return &OpenAICompatibleClient{
 		baseURL:      strings.TrimRight(baseURL, "/"),
-		apiKey:       cfg.APIKey,
 		defaultModel: cfg.Model,
 		timeout:      timeout,
 		httpClient:   client,
@@ -125,8 +123,12 @@ func (c *OpenAICompatibleClient) Generate(ctx context.Context, req domain.Genera
 		return nil, fmt.Errorf("%w: failed to create request: %v", ErrRequestFailed, err)
 	}
 	httpReq.Header.Set("Content-Type", "application/json")
-	if strings.TrimSpace(c.apiKey) != "" {
-		httpReq.Header.Set("Authorization", "Bearer "+c.apiKey)
+	if envName := strings.TrimSpace(req.Target.APIKeyEnv); envName != "" {
+		apiKey := strings.TrimSpace(os.Getenv(envName))
+		if apiKey == "" {
+			return nil, fmt.Errorf("%w: api key environment variable %q is not set", ErrInvalidRequest, envName)
+		}
+		httpReq.Header.Set("Authorization", "Bearer "+apiKey)
 	}
 
 	effectiveTimeout := c.timeout