fix: 修复实例分组无法保存的问题

direct-link（外部 .minecraft 关联）同步逻辑会把来源路径当作分组名
写入 instance_groups 表，每次同步都覆盖用户手动设置的分组，导致
分组当场生效、重启丢失。

移除三处 direct-link 相关的来源分组写入，使 instance_groups 表
专属于用户分组：
- sync_direct_link_instances: 同步时不再覆盖 groups
- create_direct_link_instance: 建实例时不再写来源分组
- launcher::promote_external_instance_link: 提升外部实例时不再写分组

packages/app-lib/src/launcher/mod.rs

@@ -1,5 +1,4 @@
 //! Logic for launching Minecraft
-use crate::api::pack::import::direct_link::direct_link_group;
 use crate::data::ModLoader;
 use crate::event::emit::{emit_instance, emit_loading, init_loading};
 use crate::event::{InstancePayloadType, LoadingBarType};
@@ -717,14 +716,6 @@ async fn promote_external_instance_link(
         &mut tx,
     )
     .await?;
-    if let Some(group) = direct_link_group(&direct.dot_minecraft) {
-        crate::state::instances::adapters::sqlite::instance_rows::replace_instance_groups(
-            &instance.id,
-            &[group],
-            &mut tx,
-        )
-        .await?;
-    }
     tx.commit().await?;
     emit_instance(&instance.id, InstancePayloadType::Edited).await?;
     Ok(())

packages/app-lib/src/state/instances/commands/create_direct_link_instance.rs

@@ -1,6 +1,6 @@
 use crate::api::pack::import::{
     ImportLauncherType,
-    direct_link::{direct_link_group, resolve_direct_link},
+    direct_link::resolve_direct_link,
 };
 use crate::launcher::ExternalGameDirMode;
 use crate::state::instances::{
@@ -156,11 +156,6 @@ pub(crate) async fn create_direct_link_instance(
         &mut tx,
     )
     .await?;
-    let groups = direct_link_group(&resolved.dot_minecraft)
-        .into_iter()
-        .collect::<Vec<_>>();
-    instance_rows::replace_instance_groups(&instance_id, &groups, &mut tx)
-        .await?;
     instance_rows::upsert_instance_launch_overrides(&launch_overrides, &mut tx)
         .await?;
     tx.commit().await?;

packages/app-lib/src/state/instances/commands/sync_direct_link_instances.rs

@@ -1,6 +1,6 @@
 use super::create_direct_link_instance::create_direct_link_instance;
 use crate::api::pack::import::direct_link::{
-    detect_direct_link_source, direct_link_group,
+    detect_direct_link_source,
     has_minecraft_version_manifest, resolve_direct_link,
 };
 use crate::event::{InstancePayloadType, emit::emit_instance};
@@ -163,11 +163,7 @@ pub(crate) async fn sync_direct_link_instances(
                 let content_changed = metadata.applied_content_set.game_version
                     != resolved.game_version
                     || metadata.applied_content_set.loader != resolved.loader;
-                let groups = direct_link_group(&resolved.dot_minecraft)
-                    .into_iter()
-                    .collect::<Vec<_>>();
-                let groups_changed = metadata.groups != groups;
-                if fields_changed || content_changed || groups_changed {
+                if fields_changed || content_changed {
                     if content_changed {
                         crate::state::edit_instance(
                             &instance.id,
@@ -216,12 +212,6 @@ pub(crate) async fn sync_direct_link_instances(
                         &mut tx,
                     )
                     .await?;
-                    instance_rows::replace_instance_groups(
-                        &instance.id,
-                        &groups,
-                        &mut tx,
-                    )
-                    .await?;
                     tx.commit().await?;
                     let _ = emit_instance(
                         &instance.id,