audit: Tier 0 quick wins — EMAIL_REDIRECT_TO prod guard + storage routing + metadata masking

Tier 0.2: src/lib/env.ts now refuses boot when NODE_ENV=production AND
EMAIL_REDIRECT_TO is set. Sendmail logs the rewrite at warn (was debug)
so dev/staging windows where someone forgets to unset are immediately
visible.

Tier 0.6: backup_jobs.storage_path added to TABLES_WITH_STORAGE_KEYS in
src/lib/storage/migrate.ts. Flipping the storage backend used to
silently orphan every pg_dump artefact — last-resort recovery path is
now actually portable.

Tier 1.7: createAuditLog now runs metadata through maskSensitiveFields
(was only applied to old/new value diffs). Portal-auth, crm-invite,
hard-delete and email-accounts services were writing raw emails into
this column unbounded.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/settings/user-settings.tsx

@@ -165,7 +165,9 @@ export function UserSettings() {
       setOriginalUsername(next ?? '');
       setUsername(next ?? '');
       setUsernameMsg(
-        next ? `Username updated. You can now sign in with @${next} or your email.` : 'Username cleared.',
+        next
+          ? `Username updated. You can now sign in with @${next} or your email.`
+          : 'Username cleared.',
       );
     } catch (err: unknown) {
       setUsernameMsg(err instanceof Error ? err.message : 'Failed to save username');
@@ -377,11 +379,13 @@ export function UserSettings() {
                 >
                   {saving === 'username' ? 'Saving…' : 'Save username'}
                 </Button>
-                {usernameMsg && <span className="text-xs text-muted-foreground">{usernameMsg}</span>}
+                {usernameMsg && (
+                  <span className="text-xs text-muted-foreground">{usernameMsg}</span>
+                )}
               </div>
               <p className="text-xs text-muted-foreground">
-                Optional alias you can use to sign in instead of your email. 2–30 lowercase
-                letters, digits, dot, underscore, or hyphen.
+                Optional alias you can use to sign in instead of your email. 2–30 lowercase letters,
+                digits, dot, underscore, or hyphen.
               </p>
             </div>
             <div className="space-y-2 pt-2 border-t">