feat: refine ruleset from a full-project field review (#39)

* feat: refine ruleset from a full-project field review

A reviewer ran ponytail across a 9-phase rewrite (protocol, PC app, simulator,
RPi daemon, ESP32 firmware) and flagged three gaps. All three land in SKILL.md
and propagate to AGENTS.md + the rule copies:

- Promote the one-runnable-check rule to a headline ("Lazy code without its
  check is unfinished"), enforced as a check-rule-copies invariant.
- Hardware carve-out in "When NOT to be lazy": a real device is never the spec
  ideal (clock drift, sensor offset), leave the calibration knob.
- Clarify the Output rule: explanation the user explicitly asked for is not
  debt, only unrequested prose is.

Fallback instructions kept in sync. Rule-copy check + tests green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* test: add a behavior gate proving the refinements actually fire

The refinements were verified as injected text, but injected != behavioral.
This adds a behavior eval that probes each refined rule on a task that should
trigger it:

- hardware    -> does the output leave a calibration knob?
- explanation -> when a write-up is explicitly requested, is it given in full?
- onecheck    -> is a runnable check left behind?

benchmarks/behavior.yaml runs the probes (baseline vs ponytail arm); the
grader benchmarks/behavior.js is proven by tests/behavior.test.js (8 cases,
RED/GREEN, no API key, runs in CI). Live-confirmed: the model under the
current ruleset passes all three gates, graded by the same grader.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/behavior.test.js

@@ -0,0 +1,80 @@
+#!/usr/bin/env node
+// Unit test for the behavior gate (benchmarks/behavior.js). Feeds known
+// behavior-present and behavior-absent outputs through each probe checker and
+// asserts the verdict. Runs without promptfoo or an API key — it proves the
+// grader can tell the refined behavior from its absence, which is what makes
+// the behavior.yaml eval trustworthy.
+
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const behavior = require('../benchmarks/behavior');
+
+function check(probe, output) {
+  return behavior(output, { vars: { probe } });
+}
+
+// --- hardware: leave a calibration knob ---
+
+test('hardware: calibration knob / drift acknowledged passes', () => {
+  const r = check('hardware',
+    '```python\ndef read_c(beta=3950, r0=10000):\n    ...\n```\n' +
+    'Notes: beta/r0 drift part-to-part, measure your own r0 at a known temp.');
+  assert.equal(r.pass, true);
+  assert.equal(r.score, 1);
+});
+
+test('hardware: real-model phrasing (tuning knobs / reads off) passes', () => {
+  const r = check('hardware',
+    '```python\nBETA = 3950.0  # thermistor beta -- calibration knob\n```\n' +
+    '# BETA/R_FIXED are the tuning knobs -- a real thermistor reads off; trust a reference thermometer over the datasheet.');
+  assert.equal(r.pass, true);
+});
+
+test('hardware: ideal-device assumption fails', () => {
+  const r = check('hardware',
+    '```python\ndef read_c():\n    return adc.read(0) * 0.1\n```\n' +
+    'Notes: converts the raw ADC reading straight to Celsius.');
+  assert.equal(r.pass, false);
+  assert.equal(r.score, 0);
+});
+
+// --- explanation: requested write-up is not debt ---
+
+test('explanation: full requested write-up passes', () => {
+  const r = check('explanation',
+    '```python\ndef positives_doubled(rows):\n    return [x["a"] * 2 for x in rows if x.get("a", 0) > 0]\n```\n' +
+    '1. Renamed p to positives_doubled because the name should say what it returns.\n' +
+    '2. Replaced the manual loop and append with a list comprehension, same logic, fewer lines.\n' +
+    '3. Used x.get("a", 0) so a missing key is treated as zero instead of raising.\n' +
+    '4. Kept the > 0 filter; the behavior is unchanged, only the shape is clearer.');
+  assert.equal(r.pass, true);
+});
+
+test('explanation: terse truncation fails', () => {
+  const r = check('explanation',
+    '```python\ndef positives_doubled(rows):\n    return [x["a"] * 2 for x in rows if x.get("a", 0) > 0]\n```\n' +
+    'skipped: the loop. comprehension covers it.');
+  assert.equal(r.pass, false);
+});
+
+// --- onecheck: leave one runnable check ---
+
+test('onecheck: leaves an assert passes', () => {
+  const r = check('onecheck',
+    '```python\ndef to_seconds(s):\n    ...\n\nassert to_seconds("1h30m") == 5400\n```');
+  assert.equal(r.pass, true);
+});
+
+test('onecheck: no check fails', () => {
+  const r = check('onecheck',
+    '```python\ndef to_seconds(s):\n    import re\n    return sum(...)\n```');
+  assert.equal(r.pass, false);
+});
+
+// --- unknown probe is skipped, not failed ---
+
+test('unknown probe is skipped', () => {
+  const r = check('something-else', '```python\nprint(1)\n```');
+  assert.equal(r.pass, true);
+  assert.match(r.reason, /skipped/i);
+});