revert: restore full config overwrite + Common Config Snippet (revert 992dda5c)

Revert the partial key-field merging refactoring introduced in 992dda5c,
along with two dependent commits (24fa8a18, 87604b18) that referenced
the now-removed ClaudeQuickToggles component.

The whitelist-based partial merge approach had critical issues:
- Non-whitelisted custom fields were lost during provider switching
- Backfill permanently stripped non-key fields from the database
- Whitelist required constant maintenance to track upstream changes

This restores the proven "full config overwrite + Common Config Snippet"
architecture where each provider stores its complete configuration and
shared settings are managed via a separate snippet mechanism.

Reverted commits:
- 24fa8a18: context-aware JSON editor hint + hide quick toggles
- 87604b18: hide ClaudeQuickToggles when creating
- 992dda5c: partial key-field merging refactoring

Restored:
- Full config snapshot write (write_live_snapshot) for Claude/Codex/Gemini
- Full config backfill (settings_config = live_config)
- Common Config Snippet UI and backend commands
- 6 frontend components/hooks for common config editing
- configApi barrel export and DB snippet methods

Removed:
- ClaudeQuickToggles component
- write_live_partial / backfill_key_fields / patch_claude_live
- All KEY_FIELDS constants

src-tauri/src/services/config.rs

@@ -1,5 +1,9 @@
+use super::provider::{sanitize_claude_settings_for_live, ProviderService};
+use crate::app_config::{AppType, MultiAppConfig};
 use crate::error::AppError;
+use crate::provider::Provider;
 use chrono::Utc;
+use serde_json::Value;
 use std::fs;
 use std::path::Path;
 
@@ -78,4 +82,150 @@ impl ConfigService {
 
         Ok(())
     }
+
+    /// 同步当前供应商到对应的 live 配置。
+    pub fn sync_current_providers_to_live(config: &mut MultiAppConfig) -> Result<(), AppError> {
+        Self::sync_current_provider_for_app(config, &AppType::Claude)?;
+        Self::sync_current_provider_for_app(config, &AppType::Codex)?;
+        Self::sync_current_provider_for_app(config, &AppType::Gemini)?;
+        Ok(())
+    }
+
+    fn sync_current_provider_for_app(
+        config: &mut MultiAppConfig,
+        app_type: &AppType,
+    ) -> Result<(), AppError> {
+        let (current_id, provider) = {
+            let manager = match config.get_manager(app_type) {
+                Some(manager) => manager,
+                None => return Ok(()),
+            };
+
+            if manager.current.is_empty() {
+                return Ok(());
+            }
+
+            let current_id = manager.current.clone();
+            let provider = match manager.providers.get(&current_id) {
+                Some(provider) => provider.clone(),
+                None => {
+                    log::warn!(
+                        "当前应用 {app_type:?} 的供应商 {current_id} 不存在，跳过 live 同步"
+                    );
+                    return Ok(());
+                }
+            };
+            (current_id, provider)
+        };
+
+        match app_type {
+            AppType::Codex => Self::sync_codex_live(config, &current_id, &provider)?,
+            AppType::Claude => Self::sync_claude_live(config, &current_id, &provider)?,
+            AppType::Gemini => Self::sync_gemini_live(config, &current_id, &provider)?,
+            AppType::OpenCode => {
+                // OpenCode uses additive mode, no live sync needed
+                // OpenCode providers are managed directly in the config file
+            }
+            AppType::OpenClaw => {
+                // OpenClaw uses additive mode, no live sync needed
+                // OpenClaw providers are managed directly in the config file
+            }
+        }
+
+        Ok(())
+    }
+
+    fn sync_codex_live(
+        config: &mut MultiAppConfig,
+        provider_id: &str,
+        provider: &Provider,
+    ) -> Result<(), AppError> {
+        let settings = provider.settings_config.as_object().ok_or_else(|| {
+            AppError::Config(format!("供应商 {provider_id} 的 Codex 配置必须是对象"))
+        })?;
+        let auth = settings.get("auth").ok_or_else(|| {
+            AppError::Config(format!("供应商 {provider_id} 的 Codex 配置缺少 auth 字段"))
+        })?;
+        if !auth.is_object() {
+            return Err(AppError::Config(format!(
+                "供应商 {provider_id} 的 Codex auth 配置必须是 JSON 对象"
+            )));
+        }
+        let cfg_text = settings.get("config").and_then(Value::as_str);
+
+        crate::codex_config::write_codex_live_atomic(auth, cfg_text)?;
+        // 注意：MCP 同步在 v3.7.0 中已通过 McpService 进行，不再在此调用
+        // sync_enabled_to_codex 使用旧的 config.mcp.codex 结构，在新架构中为空
+        // MCP 的启用/禁用应通过 McpService::toggle_app 进行
+
+        let cfg_text_after = crate::codex_config::read_and_validate_codex_config_text()?;
+        if let Some(manager) = config.get_manager_mut(&AppType::Codex) {
+            if let Some(target) = manager.providers.get_mut(provider_id) {
+                if let Some(obj) = target.settings_config.as_object_mut() {
+                    obj.insert(
+                        "config".to_string(),
+                        serde_json::Value::String(cfg_text_after),
+                    );
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn sync_claude_live(
+        config: &mut MultiAppConfig,
+        provider_id: &str,
+        provider: &Provider,
+    ) -> Result<(), AppError> {
+        use crate::config::{read_json_file, write_json_file};
+
+        let settings_path = crate::config::get_claude_settings_path();
+        if let Some(parent) = settings_path.parent() {
+            fs::create_dir_all(parent).map_err(|e| AppError::io(parent, e))?;
+        }
+
+        let settings = sanitize_claude_settings_for_live(&provider.settings_config);
+        write_json_file(&settings_path, &settings)?;
+
+        let live_after = read_json_file::<serde_json::Value>(&settings_path)?;
+        if let Some(manager) = config.get_manager_mut(&AppType::Claude) {
+            if let Some(target) = manager.providers.get_mut(provider_id) {
+                target.settings_config = live_after;
+            }
+        }
+
+        Ok(())
+    }
+
+    fn sync_gemini_live(
+        config: &mut MultiAppConfig,
+        provider_id: &str,
+        provider: &Provider,
+    ) -> Result<(), AppError> {
+        use crate::gemini_config::{env_to_json, read_gemini_env};
+
+        ProviderService::write_gemini_live(provider)?;
+
+        // 读回实际写入的内容并更新到配置中（包含 settings.json）
+        let live_after_env = read_gemini_env()?;
+        let settings_path = crate::gemini_config::get_gemini_settings_path();
+        let live_after_config = if settings_path.exists() {
+            crate::config::read_json_file(&settings_path)?
+        } else {
+            serde_json::json!({})
+        };
+        let mut live_after = env_to_json(&live_after_env);
+        if let Some(obj) = live_after.as_object_mut() {
+            obj.insert("config".to_string(), live_after_config);
+        }
+
+        if let Some(manager) = config.get_manager_mut(&AppType::Gemini) {
+            if let Some(target) = manager.providers.get_mut(provider_id) {
+                target.settings_config = live_after;
+            }
+        }
+
+        Ok(())
+    }
 }