v0.20.0 — SEQ103 argument-list tightening

SEQ103 (codegen-prose-message) now catches prose hiding inside parentheses. Previously only the outer name(...) shape was checked, so handle(the payment stuff) silenced the blocker — the cheapest evasion of the codegen gate. The rule now validates the argument list with two configurable knobs: max_arg_words (default 2) and an arg_stop_words function-word lexicon, in the same style as the other codegen lexicons. name: Type parameters and quoted literal arguments stay legal, and two-word arguments without a function word (Order order) deliberately pass — precision first. Findings state the reason: 'load_config(explicit path or auto-detect)' hides prose in its arguments ('explicit path or auto-detect' reads as 4 words).

Conforming diagrams are unaffected: zero verdict changes across the bundled examples and the calibration corpus, and golden scores are unchanged. Found by dogfooding (docs/dogfooding.md) — the second finding from that exercise to ship as a product change, after v0.19.0's suppressed-findings disclosure.