[PM-24357] Do not purge ciphers in the default collection (#6320)

* do not purge ciphers in the default collection

* Update `DeleteByOrganizationId` procedure to be more performant based on PR review feedback

* update EF integration for purge to match new SQL implementation

* update Cipher_DeleteByOrganizationId based on PR feedback from dbops team

util/Migrator/DbScripts/2025-09-22_00_ExcludeDefaultCiphersFromPurge.sql

@@ -0,0 +1,91 @@
+CREATE OR ALTER PROCEDURE [dbo].[Cipher_DeleteByOrganizationId]
+     @OrganizationId UNIQUEIDENTIFIER
+ AS
+ BEGIN
+     SET NOCOUNT ON;
+
+     DECLARE @BatchSize INT = 1000;
+
+     BEGIN TRY
+         BEGIN TRANSACTION;
+
+         ---------------------------------------------------------------------
+         -- 1. Delete organization ciphers that are NOT in any default
+         --    user collection (Collection.Type = 1).
+         ---------------------------------------------------------------------
+         WHILE 1 = 1
+         BEGIN
+             ;WITH Target AS
+             (
+                 SELECT TOP (@BatchSize) C.Id
+                 FROM dbo.Cipher C
+                 WHERE C.OrganizationId = @OrganizationId
+                   AND NOT EXISTS (
+                       SELECT 1
+                       FROM dbo.CollectionCipher CC2
+                       INNER JOIN dbo.Collection Col2
+                         ON Col2.Id = CC2.CollectionId
+                         AND Col2.Type = 1  -- Default user collection
+                       WHERE CC2.CipherId = C.Id
+                   )
+                 ORDER BY C.Id  -- Deterministic ordering (matches clustered index)
+             )
+             DELETE C
+             FROM dbo.Cipher C
+             INNER JOIN Target T ON T.Id = C.Id;
+
+             IF @@ROWCOUNT = 0 BREAK;
+         END
+
+         ---------------------------------------------------------------------
+         -- 2. Remove remaining CollectionCipher rows that reference
+         --    non-default (Type = 0 / shared) collections, for ciphers
+         --    that were preserved because they belong to at least one
+         --    default (Type = 1) collection.
+         ---------------------------------------------------------------------
+         SET @BatchSize = 1000;
+         WHILE 1 = 1
+         BEGIN
+             ;WITH ToDelete AS
+             (
+                 SELECT TOP (@BatchSize)
+                        CC.CipherId,
+                        CC.CollectionId
+                 FROM dbo.CollectionCipher CC
+                 INNER JOIN dbo.Collection Col
+                         ON Col.Id = CC.CollectionId
+                        AND Col.Type = 0  -- Non-default collections
+                 INNER JOIN dbo.Cipher C
+                         ON C.Id = CC.CipherId
+                 WHERE C.OrganizationId = @OrganizationId
+                 ORDER BY CC.CollectionId, CC.CipherId  -- Matches clustered index
+             )
+             DELETE CC
+             FROM dbo.CollectionCipher CC
+             INNER JOIN ToDelete TD
+                 ON CC.CipherId = TD.CipherId
+                AND CC.CollectionId = TD.CollectionId;
+
+             IF @@ROWCOUNT = 0 BREAK;
+         END
+
+         ---------------------------------------------------------------------
+         -- 3. Bump revision date (inside transaction for consistency)
+         ---------------------------------------------------------------------
+         EXEC [dbo].[User_BumpAccountRevisionDateByOrganizationId] @OrganizationId;
+
+         COMMIT TRANSACTION ;
+
+         ---------------------------------------------------------------------
+         -- 4. Update storage usage (outside the transaction to avoid
+         --    holding locks during long-running calculation)
+         ---------------------------------------------------------------------
+         EXEC [dbo].[Organization_UpdateStorage] @OrganizationId;
+     END TRY
+     BEGIN CATCH
+         IF @@TRANCOUNT > 0
+             ROLLBACK TRANSACTION;
+         THROW;
+     END CATCH
+ END
+ GO