feat(documents): add Epson scanner inbox and document shelf

backend/db/migrations/0073_scanner_document_inbox.sql

@@ -0,0 +1,20 @@
+CREATE TABLE "scanner_inbox_connections" (
+    "tenant_id" bigint PRIMARY KEY REFERENCES "tenants"("id") ON DELETE CASCADE,
+    "username" text NOT NULL UNIQUE,
+    "password_hash" text NOT NULL,
+    "active" boolean NOT NULL DEFAULT true,
+    "created_at" timestamp with time zone NOT NULL DEFAULT now(),
+    "updated_at" timestamp with time zone
+);
+--> statement-breakpoint
+CREATE TABLE "scanner_inbox_documents" (
+    "file_id" uuid PRIMARY KEY REFERENCES "files"("id") ON DELETE CASCADE,
+    "tenant_id" bigint NOT NULL REFERENCES "tenants"("id") ON DELETE CASCADE,
+    "remote_filename" text NOT NULL,
+    "checksum" text NOT NULL,
+    "received_at" timestamp with time zone NOT NULL DEFAULT now()
+);
+--> statement-breakpoint
+CREATE UNIQUE INDEX "scanner_inbox_documents_filename_key" ON "scanner_inbox_documents" ("tenant_id", "remote_filename");
+--> statement-breakpoint
+CREATE INDEX "scanner_inbox_documents_received_idx" ON "scanner_inbox_documents" ("tenant_id", "received_at");