Add property_overrides table + override_component enum (0221)

The per-Property fact layer deferred by ADR-0004: one row per
(property, building_part, override_component) holding the resolved
landlord-override enum as a denormalised text snapshot, plus the raw
spreadsheet description it resolved from.

Schema only — no writer yet. The bulk_upload_finaliser application will
populate it (recalculate-on-rerun via upsert on the unique key). Design
and rationale (snapshot-not-FK, drop source, recalculate semantics) in
docs/design/bulk-upload-finaliser.md.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/db/migrations/0221_nice_sumo.sql

@@ -0,0 +1,16 @@
+CREATE TYPE "public"."override_component" AS ENUM('wall_type', 'roof_type', 'property_type', 'built_form_type');--> statement-breakpoint
+CREATE TABLE "property_overrides" (
+	"id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
+	"property_id" bigint NOT NULL,
+	"portfolio_id" bigint NOT NULL,
+	"building_part" smallint NOT NULL,
+	"override_component" "override_component" NOT NULL,
+	"override_value" text NOT NULL,
+	"original_spreadsheet_description" text NOT NULL,
+	"created_at" timestamp with time zone DEFAULT now() NOT NULL,
+	"updated_at" timestamp with time zone DEFAULT now() NOT NULL,
+	CONSTRAINT "property_overrides_property_component_part_unique" UNIQUE("property_id","override_component","building_part")
+);
+--> statement-breakpoint
+ALTER TABLE "property_overrides" ADD CONSTRAINT "property_overrides_property_id_property_id_fk" FOREIGN KEY ("property_id") REFERENCES "public"."property"("id") ON DELETE cascade ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "property_overrides" ADD CONSTRAINT "property_overrides_portfolio_id_portfolio_id_fk" FOREIGN KEY ("portfolio_id") REFERENCES "public"."portfolio"("id") ON DELETE cascade ON UPDATE no action;

src/app/db/migrations/meta/_journal.json

@@ -1541,6 +1541,13 @@
       "when": 1780491109956,
       "tag": "0220_round_retro_girl",
       "breakpoints": true
+    },
+    {
+      "idx": 221,
+      "version": "7",
+      "when": 1780566543108,
+      "tag": "0221_nice_sumo",
+      "breakpoints": true
     }
   ]
 }

src/app/db/schema/property_overrides.ts

@@ -0,0 +1,68 @@
+import {
+  bigint,
+  pgEnum,
+  pgTable,
+  smallint,
+  text,
+  timestamp,
+  unique,
+  uuid,
+} from "drizzle-orm/pg-core";
+import { portfolio } from "./portfolio";
+import { property } from "./property";
+
+// The per-Property fact layer deferred by ADR-0004: one row per
+// (property, building_part, override_component) carrying the resolved enum value
+// as a denormalised snapshot. Design + rationale (Q6–Q9, snapshot-not-FK,
+// recalculate-on-rerun) live in docs/design/bulk-upload-finaliser.md.
+//
+// `override_component` values mirror the classifier category keys used in BOTH the
+// frontend (src/lib/bulkUpload/columnFields.ts) and the Model backend
+// (ClassifiableColumn.name), so the finaliser maps category → component with no
+// translation. This is the only DB-level typing left on a row — `override_value`
+// is a free-text snapshot of the resolved enum from `landlord_*_overrides`.
+export const OverrideComponentValues: [string, ...string[]] = [
+  "wall_type",
+  "roof_type",
+  "property_type",
+  "built_form_type",
+];
+
+export const overrideComponentEnum = pgEnum(
+  "override_component",
+  OverrideComponentValues,
+);
+
+export const propertyOverrides = pgTable(
+  "property_overrides",
+  {
+    id: uuid("id").defaultRandom().primaryKey(),
+    propertyId: bigint("property_id", { mode: "bigint" })
+      .notNull()
+      .references(() => property.id, { onDelete: "cascade" }),
+    portfolioId: bigint("portfolio_id", { mode: "bigint" })
+      .notNull()
+      .references(() => portfolio.id, { onDelete: "cascade" }),
+    // 0 = main building, 1 = extension 1, 2 = extension 2, … (ADR-0004 ordering).
+    buildingPart: smallint("building_part").notNull(),
+    overrideComponent: overrideComponentEnum("override_component").notNull(),
+    // Denormalised snapshot copy of the resolved enum from landlord_*_overrides.
+    overrideValue: text("override_value").notNull(),
+    // Raw spreadsheet cell text this snapshot resolved from (provenance + re-sync key).
+    originalSpreadsheetDescription: text(
+      "original_spreadsheet_description",
+    ).notNull(),
+    createdAt: timestamp("created_at", { withTimezone: true })
+      .notNull()
+      .defaultNow(),
+    updatedAt: timestamp("updated_at", { withTimezone: true })
+      .notNull()
+      .defaultNow()
+      .$onUpdate(() => new Date()),
+  },
+  (table) => ({
+    propertyComponentPartUnique: unique(
+      "property_overrides_property_component_part_unique",
+    ).on(table.propertyId, table.overrideComponent, table.buildingPart),
+  }),
+);