Pairs with the backend cabinet-unification. Directed cabinet gifts now stay
PAID/claimable, so the buyer's GiftResult must show the share link for them too.
- GiftResult.tsx: render the share state (and stop polling) for ANY claimable
paid gift via is_claimable, not just is_code_only.
- api/gift.ts: GiftPurchaseStatus gains is_claimable.
- GiftClaim.tsx: explicit failed/expired state (was falling into the 'almost
ready' spinner forever).
- PurchaseSuccess.tsx: a paid gift is always claimable — stop polling and show
the share block on `paid && is_gift` (don't gate on is_claimable, which could
strand the buyer on a spinner).
- i18n: landing.giftClaim.failedTitle/failedDesc in ru/en/zh/fa.
Pairs with the bot's unified claimable-gift model. A landing gift now lands on
the buyer's success page as PAID/claimable (deferred) instead of being delivered
to a phantom recipient, so the buyer gets a transferable link to forward and the
recipient claims it themselves — guaranteeing delivery regardless of channel or
whether they pre-exist.
- api/landings.ts: PurchaseStatus gains is_claimable/claim_url/bot_claim_link;
add GiftClaimResult + getGiftClaim()/claimGift().
- PurchaseSuccess.tsx: GiftLinkShareState — buyer sees the claim link + Telegram
link + copy-message when a gift is PAID/claimable; stop polling for that state
(it stays PAID until claimed) instead of spinning forever.
- GiftClaim.tsx (new) + /buy/gift/:token route: public recipient claim page with
a Telegram arm (GIFT_ deep link) and a web/email arm (binds + one-click login),
polling while the payment settles, idempotent "already claimed" + 404 states.
- i18n: landing.giftClaim.* / landing.giftLink.* in ru/en/zh/fa.
