post-v1: Seedelf burn-register flow #156

Summary

#155 shipped Seedelf mint / send / spend tx builders + UI. The burn-register affordance the issue listed under "UI affordances" is deferred to this follow-up.

Why deferred

Burn is a separable code path — it spends a register UTxO via the wallet validator AND mints -1 of the locator NFT via the seedelf mint validator in one tx. The verification bullets in #155 don't mention burn, and typical users have one register and never need it; folding it in would have pushed #155 over a reviewable size.

Scope

• Add burnSeedelfRegisterTx to offchain/src/seedelf/:
  • Spend the register UTxO via the existing spendFromSeedelfTx Schnorr path (ephemeral signer + external collateral or wallet collateral).
  • Add a mint action that calls the seedelf mint validator with (personal_tag = empty, amt = -1) to burn the locator NFT. The validator's amt == 1 rule does not constrain burn paths, so an empty redeemer should be accepted.
  • Send the proceeds to the user's wallet (or any caller-supplied address).
• Wire a "Burn register" button into SeedelfPanel's per-register row.
• Translate the new strings to 20 locales.
• Add a planner unit test + extend seedelf-roundtrip.test.ts with a final burn step.

Out of scope

• Bulk-burn (multiple locators in one tx).
• "Util-mint" / stealth re-mint flows. The use case is "drop a redundant locator", not "rotate keys".