refactor(web): dedup tỷ/triệu compact formatters (GOO-206)

- Add `formatCompact` as an exported alias for `formatPrice` in lib/currency.ts
- Replace 5 inline copies of the tỷ/triệu compact formatter:
  - components/map/listing-map.tsx (local `formatPrice` fn)
  - components/agents/agent-profile-client.tsx (local `fmtVND` fn)
  - app/(dashboard)/dashboard/saved-searches/page.tsx (local `formatPrice` fn)
  - app/(public)/page.tsx (local `formatVnd` fn + `vndFmt` Intl instance)
  - components/listings/price-history-chart.tsx (local `formatMillions` + `priceToMillions`)

All call sites now import from the canonical lib/currency module.
PriceHistoryChart now stores raw VND in chart data (was: millions) so
formatCompact emits correct tỷ/triệu labels using canonical thresholds.

Pre-existing test failures in inquiry/lead/AVM specs are unrelated to this change.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

prisma/migrations/20260424050000_goo196_add_retention_run_log/migration.sql

@@ -0,0 +1,25 @@
+-- GOO-196: Data retention policy & purge jobs (Decree 13 compliance)
+-- Adds the RetentionRunLog table so every purge / anonymization pass is auditable.
+
+-- CreateEnum
+CREATE TYPE "RetentionRunStatus" AS ENUM ('RUNNING', 'SUCCESS', 'PARTIAL', 'FAILED');
+
+-- CreateTable
+CREATE TABLE "RetentionRunLog" (
+    "id" TEXT NOT NULL,
+    "job" TEXT NOT NULL,
+    "phase" INTEGER,
+    "startedAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "finishedAt" TIMESTAMP(3),
+    "rowsAffected" INTEGER NOT NULL DEFAULT 0,
+    "status" "RetentionRunStatus" NOT NULL DEFAULT 'RUNNING',
+    "errorMessage" TEXT,
+    "batchSize" INTEGER,
+    "dryRun" BOOLEAN NOT NULL DEFAULT false,
+
+    CONSTRAINT "RetentionRunLog_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "RetentionRunLog_job_startedAt_idx" ON "RetentionRunLog"("job", "startedAt");
+CREATE INDEX "RetentionRunLog_startedAt_idx" ON "RetentionRunLog"("startedAt" DESC);