Add per-user learned machine profile; fix methodology honesty issues

Replaces the flat additive batch-size correction with a per-user
multiplicative pace factor learned from each account's own logged
roasts (shared/learn.js, GET /api/machine-profile), plus a lot-scoped
"last refine" auto-suggestion. Also fixes the reference data being
framed as "your own roasts" on a now-multi-user product, and
reclassifies the drying/Maillard sanity checks as informational since
they're algebraically derived from the DTR check rather than
independent (yellow = 0.56 x first crack, not entered separately).

Bug fixes found by an adversarial Opus review of the first pass:
- Unicode minus sign (U+2212) broke duration parsing against the
  app's own generated refine-suggestion text
- Printed sanity-checks table still showed a bare pass/fail glyph for
  the now-informational drying/Maillard rows
- Printed time-ledger box didn't show the pace multiplication step,
  so it stopped reconciling by hand once pace != 1
- Field 6.4 (manual batch correction) was double-counted: excluded
  from the learned-pace fit but added back after the multiplication
- Learned pace had no outlier rejection or hard clamp
- computeLedger had no test coverage
- Batch-size help copy overstated what the pace factor models (it's
  a single blanket ratio, not conditioned on batch weight)

A follow-up Opus pass also caught the per-user profile cache
surviving logout/account-switch in a shared browser; fixed by
sweeping it alongside the existing plan-draft cleanup.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

public/js/lot-picker.js

@@ -7,15 +7,35 @@ function findLot(id) {
 	return lots.find((l) => l.id === id);
 }
 
+// Matches the phrasing the app's own symptom-fix reference table uses ("First crack +0:30",
+// "First crack −0:30") — only a note in exactly that shape is safe to offer as a one-click ± Refine
+// value. Free text like "Re-weight the blend" or "Smaller batch" isn't a first-crack correction at
+// all, so it's shown for context but never auto-applied. The sign class includes the U+2212 minus
+// sign the app's own SYMPTOM_FIXES table is written with (see shared/reference-data.js) — an
+// ASCII-only class would silently refuse to recognize every slow-down correction it suggests.
+const FC_REFINE_RE = /first crack\s*([+‒–—−-]\d{1,2}:\d{2})/i;
+// The captured sign may be a non-ASCII dash; normalize to ASCII "-" before it's stored into
+// field 1.6, matching the canonical form parseDuration/formatDuration use everywhere else.
+const normalizeSign = (value) => value.replace(/^[+‒–—−]/, (c) => (c === "+" ? "+" : "-"));
+
 /** Wires the "From inventory lot" picker (in The Coffee) and the "Draw from lot" action
  * (in Roast Log — Plan vs. Actual). `getRemotePlanId` is a function since the planner's
  * remotePlanId is module-local and can change after a sync. */
-export function initLotPicker({ state, recompute, flushCurrentPlan, getRemotePlanId }) {
+export function initLotPicker({
+	state,
+	recompute,
+	flushCurrentPlan,
+	getRemotePlanId,
+	renderFormFromPlan,
+}) {
 	const select = document.getElementById("lot-select");
 	const note = document.getElementById("lot-picker-note");
 	const consumeRow = document.getElementById("inventory-consume");
 	const consumeLabel = document.getElementById("inventory-consume-label");
 	const consumeBtn = document.getElementById("btn-consume");
+	const refineBox = document.getElementById("refine-suggestion");
+	const refineText = document.getElementById("refine-suggestion-text");
+	const refineApplyBtn = document.getElementById("btn-apply-refine");
 
 	function renderOptions() {
 		const current = state.plan.inventory.lotId;
@@ -53,6 +73,7 @@ export function initLotPicker({ state, recompute, flushCurrentPlan, getRemotePla
 		}
 		renderOptions();
 		updateConsumeRow();
+		loadLastRefine(state.plan.inventory.lotId);
 	}
 
 	function updateConsumeRow() {
@@ -83,6 +104,46 @@ export function initLotPicker({ state, recompute, flushCurrentPlan, getRemotePla
 		}
 	}
 
+	// The auto-refine-carry-forward feature: closes the loop between cupping's "One change next
+	// batch" and this plan's ± Refine (1.6) instead of leaving the user to retype their own past
+	// conclusion. Never applied silently — only offered, and only when it can be parsed as an
+	// unambiguous first-crack correction (see FC_REFINE_RE above).
+	async function loadLastRefine(lotId) {
+		if (!lotId) {
+			refineBox.classList.add("hidden");
+			return;
+		}
+		let refine = null;
+		try {
+			refine = (await api(`/api/inventory/${lotId}/last-refine`)).refine;
+		} catch {
+			refine = null;
+		}
+		if (!refine?.oneChange) {
+			refineBox.classList.add("hidden");
+			return;
+		}
+		refineBox.classList.remove("hidden");
+		refineText.textContent = `Last time on this lot: "${refine.oneChange}"`;
+		const match = refine.oneChange.match(FC_REFINE_RE);
+		const value = match ? normalizeSign(match[1]) : null;
+		const currentRefine = (state.plan.fields["1.6"] || "").trim();
+		const isDefault = currentRefine === "" || currentRefine === "0";
+		if (value && isDefault) {
+			refineApplyBtn.classList.remove("hidden");
+			refineApplyBtn.textContent = `Apply ${value} to ± Refine`;
+			refineApplyBtn.onclick = () => {
+				state.plan.fields["1.6"] = value;
+				renderFormFromPlan?.();
+				recompute();
+				refineApplyBtn.classList.add("hidden");
+				showToast(`± Refine set to ${value}.`);
+			};
+		} else {
+			refineApplyBtn.classList.add("hidden");
+		}
+	}
+
 	select.addEventListener("change", () => {
 		const lotId = select.value;
 		state.plan.inventory.lotId = lotId;
@@ -102,6 +163,7 @@ export function initLotPicker({ state, recompute, flushCurrentPlan, getRemotePla
 				"Optional — link a lot and the Roast Log can draw the green weight down when you charge.";
 		}
 		updateConsumeRow();
+		loadLastRefine(lotId);
 		recompute();
 	});
 
@@ -147,5 +209,9 @@ export function initLotPicker({ state, recompute, flushCurrentPlan, getRemotePla
 	});
 
 	loadLots();
-	return { updateConsumeRow, renderOptions };
+	return {
+		updateConsumeRow,
+		renderOptions,
+		refreshRefineSuggestion: () => loadLastRefine(state.plan.inventory.lotId),
+	};
 }