perf(ai): read the deletion lock with the usage level, not on its own

The capability gate's check for an account pending deletion added a
point read of users to every request that resolves AI capabilities, one
statement over the budget on /api/auth/me, the dashboard snapshot and the
batch ingest. The usage-level read already loads the record's row once
per request; it now carries the deletion lock too.

src/lib/ai/capabilities/load.ts

@@ -41,7 +41,11 @@ import {
   type AiRecordKind,
 } from "./resolve";
 import type { AiCapabilities } from "./types";
-import { loadAiUsageState, loadRecordUsageLevel } from "./usage";
+import {
+  loadAiUsageState,
+  loadRecordAiUsage,
+  loadRecordUsageLevel,
+} from "./usage";
 
 /** Whose record, seen by whom, through which grant. */
 export interface AiCapabilityScope {
@@ -89,11 +93,8 @@ function loadActiveConsents(
  * (`src/lib/account-deletion/active-account.ts`).
  */
 async function loadRecordDeletionPending(recordId: string): Promise<boolean> {
-  const row = await prisma.user.findUnique({
-    where: { id: recordId },
-    select: { deletionRequestedAt: true },
-  });
-  return row?.deletionRequestedAt != null;
+  // The same memoised point read as the usage level.
+  return (await loadRecordAiUsage(recordId)).deletionPending;
 }
 
 function scopeKey(scope: AiCapabilityScope): string {

src/lib/ai/capabilities/usage.ts

@@ -106,6 +106,11 @@ export function loadAiUsageSettings(): Promise<AiUsageSettings> {
 export interface RecordAiUsage extends AiUsageResolution {
   preference: AiUsageLevel | null;
   settings: AiUsageSettings;
+  /**
+   * The record is pending deletion. Read in the same point read as the level,
+   * so the capability gate's deletion check costs no statement of its own.
+   */
+  deletionPending: boolean;
 }
 
 /**
@@ -118,11 +123,12 @@ export function loadRecordAiUsage(recordId: string): Promise<RecordAiUsage> {
       loadAiUsageSettings(),
       prisma.user.findUnique({
         where: { id: recordId },
-        select: { aiUsageLevel: true },
+        select: { aiUsageLevel: true, deletionRequestedAt: true },
       }),
     ]);
     const preference = usageLevelFromDb(row?.aiUsageLevel);
     return {
+      deletionPending: row?.deletionRequestedAt != null,
       ...resolveAiUsageLevel({
         preference,
         defaultLevel: settings.defaultLevel,