ops: recover stranded sBTC at SP236MA9EWHF1DN3X84EQAJEW7R6BDZZ93K3EMC3C (legacy treasury)

[whoabuddy]

Treasury was migrated from `SP236MA9EWHF1DN3X84EQAJEW7R6BDZZ93K3EMC3C` (legacy publisher address) to `SP1KGHF33817ZXW27CG50JXWC0Y6BNXAQ4E7YGAHM` in #802 as part of the x402 signal-payment rollout. The legacy address holds prior x402 classifieds revenue that needs to be recovered.

Tasks

• Locate keys / wallet for `SP236MA9...` (operator)
• Verify current sBTC balance on the legacy address
• Transfer to `SP1KGHF33...`
• Confirm zero balance and close out

Context

• Impact: payments from prior x402 classified listings — historical, not large.
• All new signal-payment + classifieds + brief revenue flows to the new address as of feat: x402 payment requirement for POST /api/signals #802 merge.
• No code change needed once funds are moved; legacy address can stay in git history as a comment in `src/lib/constants.ts`.

Refs #802.