perf(dav-collections): indexed UID lookups for single-object operations

Every CalDAV PUT/GET/DELETE of one .ics loaded the ENTIRE calendar —
every row including its ical_data — and filtered with .find() in Rust,
so importing N events cost O(N²) rows transferred. CardDAV did the exact
same in four places (PROPFIND of one .vcf, PUT existence check, GET,
DELETE), with three JSONB deserializations per discarded contact. The
indexed repo queries (find_event_by_ical_uid, get_contact_by_uid)
existed all along with zero callers.

Wire them end to end: new `get_event_by_ical_uid` /
`get_contact_by_uid` use-case methods (same access checks as
list_events / list_contacts, per the service-layer authz rule) exposed
through the storage ports and adapters, and the seven handler sites now
resolve one row instead of the whole collection.

https://claude.ai/code/session_01Dp3oWon5GBMVn4j3QXZdgx

src/interfaces/api/handlers/caldav_handler.rs

@@ -608,12 +608,13 @@ async fn handle_put(
 
     let ical_uid = extract_uid_from_ical(&ical_data);
 
+    // Indexed single-row lookup — listing the whole calendar (every row
+    // with its ical_data) to find one UID made imports O(N²).
     let existing = if let Some(ref uid) = ical_uid {
-        let events = calendar_service
-            .list_events(calendar_id, None, None, user.id)
+        calendar_service
+            .get_event_by_ical_uid(calendar_id, uid, user.id)
             .await
-            .unwrap_or_default();
-        events.into_iter().find(|e| e.ical_uid == *uid)
+            .unwrap_or_default()
     } else {
         None
     };
@@ -704,21 +705,17 @@ async fn handle_get(
             .body(Body::from(ical))
             .unwrap())
     } else {
-        // GET on individual event
+        // GET on individual event — indexed lookup by iCalendar UID.
         let event_file = parts[1];
         let ical_uid = event_file.trim_end_matches(".ics");
 
-        let events = calendar_service
-            .list_events(calendar_id, None, None, user.id)
+        let event = calendar_service
+            .get_event_by_ical_uid(calendar_id, ical_uid, user.id)
             .await
-            .map_err(|e| AppError::internal_error(format!("Failed to list events: {}", e)))?;
-
-        let event = events
-            .iter()
-            .find(|e| e.ical_uid == ical_uid)
+            .map_err(|e| AppError::internal_error(format!("Failed to look up event: {}", e)))?
             .ok_or_else(|| AppError::not_found(format!("Event not found: {}", ical_uid)))?;
 
-        let ical = generate_event_ical(event);
+        let ical = generate_event_ical(&event);
 
         Ok(Response::builder()
             .status(StatusCode::OK)
@@ -813,14 +810,11 @@ async fn handle_delete(
         let event_file = parts[1];
         let ical_uid = event_file.trim_end_matches(".ics");
 
-        let events = calendar_service
-            .list_events(calendar_id, None, None, user.id)
+        // Indexed lookup by iCalendar UID instead of listing the calendar.
+        let event = calendar_service
+            .get_event_by_ical_uid(calendar_id, ical_uid, user.id)
             .await
-            .map_err(|e| AppError::internal_error(format!("Failed to list events: {}", e)))?;
-
-        let event = events
-            .iter()
-            .find(|e| e.ical_uid == ical_uid)
+            .map_err(|e| AppError::internal_error(format!("Failed to look up event: {}", e)))?
             .ok_or_else(|| AppError::not_found(format!("Event not found: {}", ical_uid)))?;
 
         calendar_service

src/interfaces/api/handlers/carddav_handler.rs

@@ -295,19 +295,14 @@ async fn handle_propfind(
                 .body(Body::from(response_body))
                 .unwrap())
         } else {
-            // Individual contact .vcf
+            // Individual contact .vcf — indexed lookup by vCard UID.
             let contact_file = parts[1];
             let contact_uid = contact_file.trim_end_matches(".vcf");
 
-            // Look up by UID across all contacts in this address book
-            let contacts = contact_svc
-                .list_contacts(address_book_id, user.id)
+            let contact = contact_svc
+                .get_contact_by_uid(address_book_id, contact_uid, user.id)
                 .await
-                .map_err(|e| AppError::internal_error(format!("Failed to list contacts: {}", e)))?;
-
-            let contact = contacts
-                .iter()
-                .find(|c| c.uid == contact_uid)
+                .map_err(|e| AppError::internal_error(format!("Failed to look up contact: {}", e)))?
                 .ok_or_else(|| {
                     AppError::not_found(format!("Contact not found: {}", contact_uid))
                 })?;
@@ -322,8 +317,8 @@ async fn handle_propfind(
             let mut response_body = Vec::new();
             CardDavAdapter::generate_contacts_response(
                 &mut response_body,
-                std::slice::from_ref(contact),
-                &[(contact.uid.clone(), contact_to_vcard(contact))],
+                std::slice::from_ref(&contact),
+                &[(contact.uid.clone(), contact_to_vcard(&contact))],
                 &report,
                 base_href,
             )
@@ -483,13 +478,13 @@ async fn handle_put(
     // Extract UID from vCard
     let vcard_uid = extract_uid_from_vcard(&vcard_data);
 
-    // Check if contact already exists
+    // Check if contact already exists — indexed single-row lookup
+    // (listing the whole address book made imports O(N²)).
     let existing = if let Some(ref uid) = vcard_uid {
-        let contacts = contact_svc
-            .list_contacts(address_book_id, user.id)
+        contact_svc
+            .get_contact_by_uid(address_book_id, uid, user.id)
             .await
-            .unwrap_or_default();
-        contacts.into_iter().find(|c| c.uid == *uid)
+            .unwrap_or_default()
     } else {
         None
     };
@@ -579,21 +574,17 @@ async fn handle_get(
             .body(Body::from(vcf_data))
             .unwrap())
     } else {
-        // GET on individual contact
+        // GET on individual contact — indexed lookup by vCard UID.
         let contact_file = parts[1];
         let contact_uid = contact_file.trim_end_matches(".vcf");
 
-        let contacts = contact_svc
-            .list_contacts(address_book_id, user.id)
+        let contact = contact_svc
+            .get_contact_by_uid(address_book_id, contact_uid, user.id)
             .await
-            .map_err(|e| AppError::internal_error(format!("Failed to list contacts: {}", e)))?;
-
-        let contact = contacts
-            .iter()
-            .find(|c| c.uid == contact_uid)
+            .map_err(|e| AppError::internal_error(format!("Failed to look up contact: {}", e)))?
             .ok_or_else(|| AppError::not_found(format!("Contact not found: {}", contact_uid)))?;
 
-        let vcard = contact_to_vcard(contact);
+        let vcard = contact_to_vcard(&contact);
 
         Ok(Response::builder()
             .status(StatusCode::OK)
@@ -632,18 +623,14 @@ async fn handle_delete(
                 AppError::internal_error(format!("Failed to delete address book: {}", e))
             })?;
     } else {
-        // Delete contact
+        // Delete contact — indexed lookup by vCard UID.
         let contact_file = parts[1];
         let contact_uid = contact_file.trim_end_matches(".vcf");
 
-        let contacts = contact_svc
-            .list_contacts(address_book_id, user.id)
+        let contact = contact_svc
+            .get_contact_by_uid(address_book_id, contact_uid, user.id)
             .await
-            .map_err(|e| AppError::internal_error(format!("Failed to list contacts: {}", e)))?;
-
-        let contact = contacts
-            .iter()
-            .find(|c| c.uid == contact_uid)
+            .map_err(|e| AppError::internal_error(format!("Failed to look up contact: {}", e)))?
             .ok_or_else(|| AppError::not_found(format!("Contact not found: {}", contact_uid)))?;
 
         contact_svc