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/application/ports/share_ports.rs

@@ -1,3 +1,5 @@
+use uuid::Uuid;
+
 use crate::{
     application::dtos::{
         pagination::PaginatedResponseDto,
@@ -11,12 +13,12 @@ pub trait ShareUseCase: Send + Sync + 'static {
     /// Create a new shared link for a file or folder
     async fn create_shared_link(
         &self,
-        user_id: &str,
+        user_id: Uuid,
         dto: CreateShareDto,
     ) -> Result<ShareDto, DomainError>;
 
     /// Get a shared link by its ID (ownership-verified)
-    async fn get_shared_link(&self, id: &str, requester_id: &str) -> Result<ShareDto, DomainError>;
+    async fn get_shared_link(&self, id: Uuid, requester_id: Uuid) -> Result<ShareDto, DomainError>;
 
     /// Get a shared link by its token (for access by non-users)
     async fn get_shared_link_by_token(&self, token: &str) -> Result<ShareDto, DomainError>;
@@ -26,24 +28,24 @@ pub trait ShareUseCase: Send + Sync + 'static {
         &self,
         item_id: &str,
         item_type: &ShareItemType,
-        requester_id: &str,
+        requester_id: Uuid,
     ) -> Result<Vec<ShareDto>, DomainError>;
 
     /// Update a shared link (ownership-verified)
     async fn update_shared_link(
         &self,
-        id: &str,
-        requester_id: &str,
+        id: Uuid,
+        requester_id: Uuid,
         dto: UpdateShareDto,
     ) -> Result<ShareDto, DomainError>;
 
     /// Delete a shared link (ownership-verified)
-    async fn delete_shared_link(&self, id: &str, requester_id: &str) -> Result<(), DomainError>;
+    async fn delete_shared_link(&self, id: Uuid, requester_id: Uuid) -> Result<(), DomainError>;
 
     /// Get all shared links created by a specific user
     async fn get_user_shared_links(
         &self,
-        user_id: &str,
+        user_id: Uuid,
         page: usize,
         per_page: usize,
     ) -> Result<PaginatedResponseDto<ShareDto>, DomainError>;
@@ -77,19 +79,19 @@ pub trait ShareStoragePort: Send + Sync + 'static {
     /// (prevents share-ID enumeration).
     async fn find_share_by_id_for_user(
         &self,
-        id: &str,
-        user_id: &str,
+        id: Uuid,
+        user_id: Uuid,
     ) -> Result<crate::domain::entities::share::Share, DomainError>;
 
     /// Delete a share only if it belongs to the given user.
-    async fn delete_share_for_user(&self, id: &str, user_id: &str) -> Result<(), DomainError>;
+    async fn delete_share_for_user(&self, id: Uuid, user_id: Uuid) -> Result<(), DomainError>;
 
     /// Find shares for a specific item that belong to the given user.
     async fn find_shares_by_item_for_user(
         &self,
         item_id: &str,
         item_type: &ShareItemType,
-        user_id: &str,
+        user_id: Uuid,
     ) -> Result<Vec<crate::domain::entities::share::Share>, DomainError>;
 
     async fn update_share(
@@ -99,7 +101,7 @@ pub trait ShareStoragePort: Send + Sync + 'static {
 
     async fn find_shares_by_user(
         &self,
-        user_id: &str,
+        user_id: Uuid,
         offset: usize,
         limit: usize,
     ) -> Result<(Vec<crate::domain::entities::share::Share>, usize), DomainError>;