fix(openai): bump codex CLI version from 0.104.0 to 0.125.0

The hardcoded codex CLI version (0.104.0) causes upstream rejection
when using gpt-5.5 with compact, as the server treats the request
as an outdated client and returns 400/502.

Update codexCLIVersion, codexCLIUserAgent, and openAICodexProbeVersion
to 0.125.0 to match the current Codex CLI release.

Fixes #1933, #1887, #1865
Related: #1609, #1298, #849

backend/internal/service/openai_gateway_service.go

@@ -40,7 +40,7 @@ const (
 	// OpenAI Platform API for API Key accounts (fallback)
 	openaiPlatformAPIURL   = "https://api.openai.com/v1/responses"
 	openaiStickySessionTTL = time.Hour // 粘性会话TTL
-	codexCLIUserAgent      = "codex_cli_rs/0.104.0"
+	codexCLIUserAgent      = "codex_cli_rs/0.125.0"
 	// codex_cli_only 拒绝时单个请求头日志长度上限（字符）
 	codexCLIOnlyHeaderValueMaxBytes = 256
 
@@ -54,7 +54,7 @@ const (
 	openAIWSRetryBackoffMaxDefault     = 2 * time.Second
 	openAIWSRetryJitterRatioDefault    = 0.2
 	openAICompactSessionSeedKey        = "openai_compact_session_seed"
-	codexCLIVersion                    = "0.104.0"
+	codexCLIVersion                    = "0.125.0"
 	// Codex 限额快照仅用于后台展示/诊断，不需要每个成功请求都立即落库。
 	openAICodexSnapshotPersistMinInterval = 30 * time.Second
 )