feat: guard fee-based token sends on hardware wallets

[raul-oliveira]

Acceptance Criteria

• On a hardware wallet, clicking Send Tokens with a fee-based token shows the "Action not supported" modal and blocks the send, instead of letting the Ledger reject the transaction with a cryptic "Error communicating with Ledger".
• Software wallets are unaffected: fee-based tokens still send normally.
• Hardware wallets sending HTR / deposit tokens keep the existing Ledger flow untouched.

Context

The Hathor Ledger app cannot deserialize a transaction that carries a fee header: getDataToSign() appends the FeeHeader bytes after the outputs, and the device's parser rejects the trailing bytes (SW_INVALID_TX). Until the Ledger app learns to parse headers, we block the send early with a clear message, mirroring the existing isLedgerCustomTokenAllowed() guard and reusing the ALERT_NOT_SUPPORTED modal.

The token is detected as fee-based via its version (TokenVersion.FEE), read from the Redux tokens list (kept fresh by useTokensDetails).

Screenshots

Security Checklist

• Make sure you do not include new dependencies in the project unless strictly necessary and do not include dev-dependencies as production ones. — No new dependencies; single-file change in src/screens/SendTokens.js.

Summary by CodeRabbit

• Bug Fixes
  • Hardware wallet users can no longer attempt to send fee-based tokens.
  • Added a clear alert instructing users to switch to a software wallet before continuing.

[coderabbitai]

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: blocking fee-based token sends on hardware wallets.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch raul-oliveira/feat/ledger-fee-token-guard

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