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/services/recent_service.rs

@@ -4,6 +4,7 @@ use crate::common::errors::{DomainError, ErrorKind, Result};
 use crate::infrastructure::repositories::pg::RecentItemsPgRepository;
 use std::sync::Arc;
 use tracing::info;
+use uuid::Uuid;
 
 /// Implementation of the use case for managing recent items.
 ///
@@ -28,7 +29,7 @@ impl RecentItemsUseCase for RecentService {
     /// Get recent items for a user
     async fn get_recent_items(
         &self,
-        user_id: &str,
+        user_id: Uuid,
         limit: Option<i32>,
     ) -> Result<Vec<RecentItemDto>> {
         info!("Getting recent items for user: {}", user_id);
@@ -47,7 +48,7 @@ impl RecentItemsUseCase for RecentService {
     /// Record access to an item
     async fn record_item_access(
         &self,
-        user_id: &str,
+        user_id: Uuid,
         item_id: &str,
         item_type: &str,
     ) -> Result<()> {
@@ -77,7 +78,7 @@ impl RecentItemsUseCase for RecentService {
     /// Remove an item from recent
     async fn remove_from_recent(
         &self,
-        user_id: &str,
+        user_id: Uuid,
         item_id: &str,
         item_type: &str,
     ) -> Result<bool> {
@@ -101,7 +102,7 @@ impl RecentItemsUseCase for RecentService {
     }
 
     /// Clear all recent items
-    async fn clear_recent_items(&self, user_id: &str) -> Result<()> {
+    async fn clear_recent_items(&self, user_id: Uuid) -> Result<()> {
         info!("Clearing all recent items for user {}", user_id);
         self.repo.clear_all(user_id).await?;
         info!("Cleared all recent items for user {}", user_id);