fix(pay): read a settlement clause standing on its own as the method

[iliasabk]

readPayLine reads "…, settled in SOL" / "via bank transfer" / "paid in USDC" off the end of a line and returns it as the method. normalisePay then splits a string pay field on newlines and ; before handing each piece to readPayLine — so the moment the settlement clause stands on its own, the whole pay is refused with Could not find an amount in "", an error that quotes an empty string and names nothing.

So all of these were rejected while the same clause inline on a line parses fine:

• pay: "$0.25 per task; settled in SOL" — the ; is the documented line separator and the same mark SETTLED itself tolerates in front of the clause ([,;]?), which made the clause's own syntax unreachable in the string form.
• pay: "$0.25 per task\nsettled in SOL" — a clause per line is exactly how the one-line-per-price box invites the text to be written.
• pay: ["$100 an hour", "via bank transfer"] — the array form an API client naturally produces.
• pay: [{ text: "paid in USDC" }, { text: "$5k fixed" }] — same for the object-text form.

A standalone clause that names a recognised coin or rail now becomes the method (namedMethod, first one wins, an explicit payMethod still overrides it, as before). A clause naming anything else — in London, paid in magic beans — still refuses the pay, now quoting the clause text itself.

Covered by test/pay-standalone-method.test.ts: the ;, newline, array-entry and {text} forms all read as method + one line, a clause before the lines works, unrecognised words still refuse, payMethod still wins, and unpaid on its own line still clears the lines.

tsc clean, node --test — 366/366 pass.

Submitted under the current paid Agentic Jobs bug-fix offer.