perf: migrate all user/session/auth IDs from VARCHAR(36) to native UUID

- Schema: all ~15 VARCHAR(36) columns → UUID with DEFAULT gen_random_uuid()
- Domain entities: User, Session, DeviceCode, AppPassword, Share → id: Uuid
- DTOs: CurrentUser.id → Uuid (API boundary DTOs keep String for JSON)
- Auth middleware: parse JWT claims.sub (String) → Uuid at boundary
- All repository traits, port traits, service impls updated end-to-end
- Handlers: pass Uuid by value (Copy, 16 bytes) instead of String refs
- Settings chain: updated_by column → Uuid (was text, caused setup crash)
- Removed ~650 lines of String↔Uuid conversion boilerplate
- Eliminates per-request heap allocations for ID cloning
- 16-byte binary comparison vs 36-byte string comparison in all queries
- Native UUID indexing in PostgreSQL (btree on 16 bytes vs 36-char text)

85 files changed, 1090 insertions(+), 1739 deletions(-)

src/interfaces/api/handlers/recent_handler.rs

@@ -25,7 +25,7 @@ pub async fn get_recent_items(
     auth_user: AuthUser,
     Query(params): Query<GetRecentParams>,
 ) -> impl IntoResponse {
-    let user_id = &auth_user.id;
+    let user_id = auth_user.id;
 
     match recent_service.get_recent_items(user_id, params.limit).await {
         Ok(items) => {
@@ -51,7 +51,7 @@ pub async fn record_item_access(
     auth_user: AuthUser,
     Path((item_type, item_id)): Path<(String, String)>,
 ) -> impl IntoResponse {
-    let user_id = &auth_user.id;
+    let user_id = auth_user.id;
 
     // Validate item type
     if item_type != "file" && item_type != "folder" {
@@ -97,7 +97,7 @@ pub async fn remove_from_recent(
     auth_user: AuthUser,
     Path((item_type, item_id)): Path<(String, String)>,
 ) -> impl IntoResponse {
-    let user_id = &auth_user.id;
+    let user_id = auth_user.id;
 
     match recent_service
         .remove_from_recent(user_id, &item_id, &item_type)
@@ -142,7 +142,7 @@ pub async fn clear_recent_items(
     State(recent_service): State<Arc<RecentService>>,
     auth_user: AuthUser,
 ) -> impl IntoResponse {
-    let user_id = &auth_user.id;
+    let user_id = auth_user.id;
 
     match recent_service.clear_recent_items(user_id).await {
         Ok(_) => {