refactor: standardize constant naming and improve file-based auth handling

- Renamed constants from uppercase to CamelCase for consistency.
- Replaced redundant file-based auth handling logic with the new `util.CountAuthFiles` helper.
- Fixed various error-handling inconsistencies and enhanced robustness in file operations.
- Streamlined auth client reload logic in server and watcher components.
- Applied minor code readability improvements across multiple packages.

internal/runtime/executor/gemini_executor.go

@@ -8,6 +8,7 @@ import (
 	"io"
 	"net/http"
 
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
@@ -20,9 +21,11 @@ const (
 
 // GeminiExecutor is a stateless executor for the official Gemini API using API keys.
 // If no API key is found on the auth entry, it falls back to the legacy client via ClientAdapter.
-type GeminiExecutor struct{}
+type GeminiExecutor struct {
+	cfg *config.Config
+}
 
-func NewGeminiExecutor() *GeminiExecutor { return &GeminiExecutor{} }
+func NewGeminiExecutor(cfg *config.Config) *GeminiExecutor { return &GeminiExecutor{cfg: cfg} }
 
 func (e *GeminiExecutor) Identifier() string { return "gemini" }
 
@@ -51,6 +54,7 @@ func (e *GeminiExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, r
 		url = url + fmt.Sprintf("?$alt=%s", opts.Alt)
 	}
 
+	recordAPIRequest(ctx, e.cfg, body)
 	httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
 	if err != nil {
 		return cliproxyexecutor.Response{}, err
@@ -73,12 +77,14 @@ func (e *GeminiExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, r
 	defer func() { _ = resp.Body.Close() }()
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
 		b, _ := io.ReadAll(resp.Body)
+		appendAPIResponseChunk(ctx, e.cfg, b)
 		return cliproxyexecutor.Response{}, statusErr{code: resp.StatusCode, msg: string(b)}
 	}
 	data, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return cliproxyexecutor.Response{}, err
 	}
+	appendAPIResponseChunk(ctx, e.cfg, data)
 	var param any
 	out := sdktranslator.TranslateNonStream(ctx, to, from, req.Model, bytes.Clone(opts.OriginalRequest), body, data, &param)
 	return cliproxyexecutor.Response{Payload: []byte(out)}, nil
@@ -101,6 +107,7 @@ func (e *GeminiExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.A
 	} else {
 		url = url + fmt.Sprintf("?$alt=%s", opts.Alt)
 	}
+	recordAPIRequest(ctx, e.cfg, body)
 	httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
 	if err != nil {
 		return nil, err
@@ -123,6 +130,7 @@ func (e *GeminiExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.A
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
 		defer func() { _ = resp.Body.Close() }()
 		b, _ := io.ReadAll(resp.Body)
+		appendAPIResponseChunk(ctx, e.cfg, b)
 		return nil, statusErr{code: resp.StatusCode, msg: string(b)}
 	}
 	out := make(chan cliproxyexecutor.StreamChunk)
@@ -135,6 +143,7 @@ func (e *GeminiExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.A
 		var param any
 		for scanner.Scan() {
 			line := scanner.Bytes()
+			appendAPIResponseChunk(ctx, e.cfg, line)
 			lines := sdktranslator.TranslateStream(ctx, to, from, req.Model, bytes.Clone(opts.OriginalRequest), body, bytes.Clone(line), &param)
 			for i := range lines {
 				out <- cliproxyexecutor.StreamChunk{Payload: []byte(lines[i])}