feat(account): accept a third gender value

Add "OTHER" to the accepted gender values (the column is a free String, so no
migration) and surface it in the account selector. This lets a non-binary or
trans user record their gender and opt into the cycle-tracking surface through
the per-user enable flag, rather than being gated out by a binary field.

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

src/components/settings/account-section.tsx

@@ -448,6 +448,7 @@ export function AccountSection() {
                 <option value="">{t("settings.genderNone")}</option>
                 <option value="MALE">{t("settings.genderMale")}</option>
                 <option value="FEMALE">{t("settings.genderFemale")}</option>
+                <option value="OTHER">{t("settings.genderOther")}</option>
               </NativeSelect>
               <p className="text-muted-foreground text-xs">
                 {t("settings.genderHint")}