fix(codex): fix 404 errors and connection timeout with custom base_url (#760)

* fix(proxy): fix Codex 404 errors with custom base_url prefixes

- handlers.rs:268: Remove hardcoded /v1 prefix in Codex forwarding
- codex.rs:140: Only add /v1 for origin-only base_urls, dedupe /v1/v1
- stream_check.rs:364: Try /responses first, fallback to /v1/responses
- provider.rs:427: Don't force /v1 for custom prefix base_urls

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(codex): always add /v1 for custom prefix base_urls

Changed logic to always add /v1 prefix unless base_url already ends with /v1.
This fixes 504 timeout errors with relay services that expect /v1 in the path.

- Most relay services follow OpenAI standard format: /v1/responses
- Users can opt-out by adding /v1 to their base_url configuration
- Updated test case to reflect new behavior

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(proxy): allow system proxy on localhost with different ports

- Only bypass system proxy if it points to CC Switch's own port (15721)
- Allow other localhost proxies (e.g., Clash on 7890) to be used
- Add INFO level logging for request URLs to aid debugging

This fixes connection timeout issues when using local proxy tools.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(codex): don't add /v1 for custom prefix base_urls

Reverted logic to not add /v1 for base_urls with custom prefixes.
Many relay services use custom paths without /v1.

- Pure origin (e.g., https://api.openai.com) → adds /v1
- With /v1 (e.g., https://api.openai.com/v1) → no change
- Custom prefix (e.g., https://example.com/openai) → no /v1

This fixes 404 errors with relay services that don't use /v1 in their paths.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(proxy): use dynamic port for system proxy detection

Instead of hardcoding port 15721, now uses the actual configured
listen_port from proxy settings.

- Added set_proxy_port() to update the port when proxy server starts
- Added get_proxy_port() to retrieve current port for detection
- Updated server.rs to call set_proxy_port() on startup
- Updated tests to reflect new behavior

This allows users to change the proxy port in settings without
breaking the system proxy detection logic.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(proxy): change default proxy port from 15721 to 5000

Update the default fallback port in get_proxy_port() from 15721 to 5000
to match the project's standard default port configuration.

Also updated test cases to use port 5000 consistently.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(proxy): revert default port back to 15721

Revert the default fallback port in get_proxy_port() from 5000 back to 15721
to align with the project's updated default port configuration.

Also updated test cases to use port 15721 consistently.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

---------

Co-authored-by: ozbombor <ozbombor@users.noreply.github.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

src-tauri/src/provider.rs

@@ -441,11 +441,18 @@ impl UniversalProvider {
             .and_then(|m| m.reasoning_effort.clone())
             .unwrap_or_else(|| "high".to_string());
 
-        // 确保 base_url 以 /v1 结尾（Codex 使用 OpenAI 兼容 API）
-        let codex_base_url = if self.base_url.ends_with("/v1") {
-            self.base_url.clone()
+        // Codex/OpenAI 的 base_url 既可能是纯 origin（需要补 /v1），也可能包含自定义前缀（不应强行补版本）
+        let base_trimmed = self.base_url.trim_end_matches('/');
+        let origin_only = match base_trimmed.split_once("://") {
+            Some((_scheme, rest)) => !rest.contains('/'),
+            None => !base_trimmed.contains('/'),
+        };
+        let codex_base_url = if base_trimmed.ends_with("/v1") {
+            base_trimmed.to_string()
+        } else if origin_only {
+            format!("{base_trimmed}/v1")
         } else {
-            format!("{}/v1", self.base_url.trim_end_matches('/'))
+            base_trimmed.to_string()
         };
 
         // 生成 Codex 的 config.toml 内容
@@ -521,6 +528,54 @@ requires_openai_auth = true"#
     }
 }
 
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn universal_codex_provider_origin_base_url_adds_v1() {
+        let mut p = UniversalProvider::new(
+            "id".to_string(),
+            "Test".to_string(),
+            "custom".to_string(),
+            "https://api.openai.com".to_string(),
+            "sk-test".to_string(),
+        );
+        p.apps.codex = true;
+
+        let provider = p.to_codex_provider().expect("should build codex provider");
+        let toml = provider
+            .settings_config
+            .get("config")
+            .and_then(|v| v.as_str())
+            .expect("config should be a toml string");
+
+        assert!(toml.contains("base_url = \"https://api.openai.com/v1\""));
+    }
+
+    #[test]
+    fn universal_codex_provider_custom_prefix_does_not_force_v1() {
+        let mut p = UniversalProvider::new(
+            "id".to_string(),
+            "Test".to_string(),
+            "custom".to_string(),
+            "https://example.com/openai".to_string(),
+            "sk-test".to_string(),
+        );
+        p.apps.codex = true;
+
+        let provider = p.to_codex_provider().expect("should build codex provider");
+        let toml = provider
+            .settings_config
+            .get("config")
+            .and_then(|v| v.as_str())
+            .expect("config should be a toml string");
+
+        assert!(toml.contains("base_url = \"https://example.com/openai\""));
+        assert!(!toml.contains("https://example.com/openai/v1"));
+    }
+}
+
 // ============================================================================
 // OpenCode 供应商配置结构
 // ============================================================================