Desactiva auto-dedup (pérdida de datos cross-device) + forward-fill en gráficas de evolution

CRÍTICO: el auto-dedup de build 68 borraba entidades padre con regla Cascade
(Account/Category). Al propagarse el delete por CloudKit, otros dispositivos
aplicaban la cascada al importar ANTES de la reasignación de hijos → wipe de
sources/snapshots. Vació iPhone y iPad. Quitadas las llamadas automáticas a
cleanupLogicalDuplicates() en processRemoteChanges y en la carga; el UUID-dedup
seguro se mantiene. Métodos quedan definidos para un rediseño CloudKit-safe.

Gráficas: forward-fill por source en evolution/allocation/period para que el
total de cada mes refleje el último valor de CADA source (no solo las
actualizadas ese mes) y el último punto coincida con el total del portfolio.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01L2p3gUZRNWW388rWFRjiU7

PortfolioJournal/Models/CoreDataStack.swift

@@ -213,11 +213,12 @@ class CoreDataStack: ObservableObject {
             }
             DispatchQueue.main.async {
                 self?.isLoaded = true
-                // Collapse any logical duplicates already sitting in the local store
-                // (per-device default accounts/categories piled up by earlier syncs).
-                // Runs once at launch so an existing mess is cleaned even if no new
-                // remote change arrives this session.
-                self?.cleanupLogicalDuplicates()
+                // NOTE: automatic logical dedup DISABLED. Deleting cascade-parent
+                // entities (Account/Category) and letting those deletes propagate via
+                // CloudKit can trigger the Cascade delete rule on OTHER devices before
+                // the child-reassignment transaction imports — cascade-wiping sources
+                // and snapshots. This caused total data loss across devices on build 68.
+                // Dedup must be redesigned to be CloudKit-safe before re-enabling.
                 MonthlyCheckInStore.migrateIfNeeded()
                 // Migrate device-local UserDefaults data into Core Data so it syncs via iCloud.
                 MonthlyContributionStore.migrateIfNeeded(context: container.viewContext)
@@ -506,14 +507,9 @@ class CoreDataStack: ObservableObject {
             if removed > 0 {
                 print("[RemoteChanges] Removed \(removed) duplicate objects after CloudKit import")
             }
-            // Then collapse *logical* duplicates (same entity, different UUIDs) —
-            // e.g. per-device default accounts/categories, or a dataset that was
-            // seeded independently in two environments. UUID dedup above can't see
-            // these because the UUIDs differ.
-            let logical = self.cleanupLogicalDuplicates()
-            if logical > 0 {
-                print("[RemoteChanges] Removed \(logical) logical duplicate objects after CloudKit import")
-            }
+            // NOTE: automatic logical dedup DISABLED here on purpose — see the load
+            // block. Deleting cascade-parent entities and propagating those deletes
+            // via CloudKit cascade-wiped children on other devices (build 68 incident).
             // Notify repositories to re-fetch unconditionally.
             NotificationCenter.default.post(name: .cloudKitForceReload, object: nil)
             self.objectWillChange.send()