fix(lite): require a confirmed 8+ character passphrase to encrypt

The Lite "Encrypt wallet" field and the Create/Restore passphrase had no
confirmation and no minimum length; only an empty passphrase was
refused. Encrypting locks the wallet at once, and a locked wallet cannot
reveal its seed, so a typo there could cost a user without a seed backup
their funds. The full-node encrypt dialog already requires 8 characters
and a confirmation.

This applies to new passphrases only. Opening and unlocking are
unchanged: an existing wallet with a shorter passphrase still opens and
unlocks.

- A pure liteEncryptPassphraseValid(pass, confirm): at least 8 bytes and
  equal to the confirmation. It takes string_views, so the page's secret
  buffers are never copied.
- liteLifecyclePassphraseAcceptable(op, pass, confirm) gates the Settings
  create/open/restore request. Open is never checked, because its
  passphrase field also unlocks an existing wallet. Create and Restore
  are checked only when a passphrase was entered; an empty one still
  creates an unencrypted wallet.
- Encrypt gets a Confirm field. The button stays disabled until the
  passphrase is valid, and a hint says why (too short, with the count,
  or not matching).
- Create/Restore show a Confirm row once a passphrase is typed, with the
  same hint. Validate stays disabled while the passphrase is invalid, so
  a click never wipes a typed seed over a passphrase typo. The request
  builder re-checks the rule.
- The confirmation buffers are wiped with their passphrase: after a run
  or an encrypt, and when the Confirm row is hidden.
- Once the wallet is closed, the Settings page wipes the Encrypt,
  Confirm and Decrypt passphrase buffers whole every time, also when no
  secret was revealed; before, closing the wallet wiped them only while
  clearing a revealed backup or secret. They are zeroed in full because
  an emptied field can still hold the old tail past its first NUL.
- New copy under Encrypt: "Anyone with the wallet file can try
  passphrases offline. Back up your seed phrase first and use a long
  passphrase."
- i18n: three new keys (lite_confirm_label, tt_lite_confirm_pass,
  lite_encrypt_offline_warning) in i18n.cpp and the 8 language files,
  added additively. The hints reuse the wizard's wiz_pass_too_short and
  wiz_pass_mismatch. No new CJK glyphs, so the subset font is unchanged.

Tests: the validator rejects empty, short (7) and mismatched or
unconfirmed passphrases, and accepts 8 or more with a match. The request
gate always accepts Open, even "abc" with no confirmation, accepts
Create/Restore without a passphrase, and applies the rule to them
otherwise. An encrypted, locked wallet still opens and unlocks through
the controller with the 3-character passphrase "abc".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/wallet/lite_wallet_lifecycle_ui_adapter.cpp

@@ -1,7 +1,26 @@
 #include "lite_wallet_lifecycle_ui_adapter.h"
 
-// The lite-wallet lifecycle UI adapter is now header-only: it declares the live
-// LiteWalletLifecycleUiExecutionInput DTO (and its request-intent / prerequisites
-// sub-structs) that Settings drives the App-owned controller with. The former
-// dry-run "readiness" executor and its status/issue reporting were removed as dead
-// scaffolding, leaving no out-of-line definitions in this translation unit.
+// The lite-wallet lifecycle UI adapter declares the live LiteWalletLifecycleUiExecutionInput DTO
+// (and its request-intent / prerequisites sub-structs) that Settings drives the App-owned
+// controller with. The former dry-run "readiness" executor and its status/issue reporting were
+// removed as dead scaffolding. The only out-of-line definitions here are the pure passphrase rules
+// Settings applies to NEW passphrases.
+
+namespace dragonx {
+namespace wallet {
+
+bool liteEncryptPassphraseValid(std::string_view pass, std::string_view confirm)
+{
+    return pass.size() >= kLiteMinNewPassphraseLength && pass == confirm;
+}
+
+bool liteLifecyclePassphraseAcceptable(LiteWalletLifecycleOperation operation,
+                                       std::string_view pass, std::string_view confirm)
+{
+    if (operation == LiteWalletLifecycleOperation::OpenExisting) return true;
+    if (pass.empty()) return true;
+    return liteEncryptPassphraseValid(pass, confirm);
+}
+
+} // namespace wallet
+} // namespace dragonx