Refactor tonapi module: Move account and transaction logic to services

- Moved account-related functions and classes from `pyfragment.domains.tonapi.account` to `pyfragment.services.tonapi.account`.
- Moved transaction-related functions and classes from `pyfragment.domains.tonapi.transaction` to `pyfragment.services.tonapi.transaction`.
- Updated imports across the codebase to reflect the new structure.
- Removed unused `tonapi` module files and cleaned up related code.
- Introduced `ApiProvider` enum to manage API provider types.
- Added validation functions for cookies and wallet versions in a new `validation.py` module.

pyfragment/core/constants.py

@@ -82,6 +82,3 @@ PREMIUM_MONTHS_VALID: frozenset[int] = frozenset({3, 6, 12})
 
 # Mnemonic phrase valid word counts
 MNEMONIC_WORD_COUNTS_VALID: frozenset[int] = frozenset({12, 24})
-
-# Tonapi API key minimum length (tonapi.io)
-TONAPI_KEY_MIN_LENGTH: int = 68

pyfragment/core/validation.py

@@ -0,0 +1,58 @@
+from __future__ import annotations
+
+import json
+from typing import Any, cast
+
+from pyfragment.core.constants import MNEMONIC_WORD_COUNTS_VALID, REQUIRED_COOKIE_KEYS
+from pyfragment.enums import ApiProvider, WalletVersion
+from pyfragment.exceptions import ConfigurationError, CookieError
+
+
+def parse_cookies(cookies: dict[str, Any] | str) -> dict[str, Any]:
+    if isinstance(cookies, str):
+        try:
+            cookies = json.loads(cookies)
+        except Exception as exc:
+            raise CookieError(CookieError.READ_FAILED.format(exc=exc)) from exc
+    return cast(dict[str, Any], cookies)
+
+
+def validate_cookie_keys(cookies: dict[str, Any]) -> None:
+    missing = [k for k in REQUIRED_COOKIE_KEYS if not str(cookies.get(k, "")).strip()]
+    if missing:
+        raise CookieError(CookieError.MISSING_KEYS.format(keys=", ".join(missing)))
+
+
+def normalize_provider(api_provider: str) -> ApiProvider:
+    try:
+        return ApiProvider(api_provider.strip().lower())
+    except ValueError:
+        raise ConfigurationError(
+            ConfigurationError.UNSUPPORTED_PROVIDER.format(
+                provider=api_provider,
+                supported=", ".join(sorted(p.value for p in ApiProvider)),
+            )
+        )
+
+
+def normalize_wallet_version(wallet_version: str) -> WalletVersion:
+    version = wallet_version.strip().upper()
+    try:
+        return WalletVersion(version)
+    except ValueError:
+        raise ConfigurationError(
+            ConfigurationError.UNSUPPORTED_VERSION.format(
+                version=version,
+                supported=", ".join(sorted(m.value for m in WalletVersion)),
+            )
+        )
+
+
+def validate_credentials(seed: str, api_key: str) -> None:
+    missing = [name for name, val in (("seed", seed), ("api_key", api_key)) if not val or not str(val).strip()]
+    if missing:
+        raise ConfigurationError(ConfigurationError.MISSING_VARS.format(keys=", ".join(missing)))
+
+    word_count = len(seed.split())
+    if word_count not in MNEMONIC_WORD_COUNTS_VALID:
+        raise ConfigurationError(ConfigurationError.INVALID_MNEMONIC.format(count=word_count))