feat: migrate smart-updown contract to SPL-token (фантики)

- create_bet: escrow фантиков с bettor на vault (PDA[global,vault]) через anchor_spl::token
- close_bet: выплата фантиков из vault на bettor (CPI с signer_seeds vault)
- state/constants: comments про единицы (token units decimals=6), + VAULT_SEED
- IDL регенерирован (idl/ + relayer/idl/) с аккаунтами bettor_token/vault_token/token_program
- тесты обновлены под токен (10/10 + doctest)

program/programs/smart-updown/src/constants.rs

@@ -6,6 +6,11 @@ pub const GLOBAL_SEED: &[u8] = b"global";
 #[constant]
 pub const BET_SEED: &[u8] = b"bet";
 
+/// Vault PDA seed: the token vault lives at PDA([GLOBAL_SEED, VAULT_SEED]).
+/// It cannot reuse GLOBAL_SEED alone — that PDA address is the `global` state account itself.
+#[constant]
+pub const VAULT_SEED: &[u8] = b"vault";
+
 pub const SIDE_UP: u64 = 0;
 pub const SIDE_DOWN: u64 = 1;