Add admin LLM model setting; rename Pi to LLM in the UI; drop table Review column

- New server/llm.js consolidates ModelRuntime + model selection: admin
  setting (app_settings.llm_model) > LLM_MODEL/PREFILL_MODEL env > first
  available; used by both prefill and roast evaluation
- GET/PUT /api/admin/llm lists configured models and stores the choice
  (validated against the list; empty = auto; audited); admin page gains
  an LLM section with a model picker
- All user-facing 'Pi agent' wording is now 'LLM'; no_model error message
  no longer references the pi CLI
- /roasts table: Review column removed (review lives in the detail view)

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

server/app.js

@@ -7,6 +7,7 @@ import { runPrefill } from "./prefill.js";
 import { parseAlog } from "./alog.js";
 import { listAlogLibrary, readAlogFromLibrary } from "./alog-library.js";
 import { evaluateRoast as defaultEvaluateRoast } from "./evaluate-roast.js";
+import { listAvailableModels as defaultListModels } from "./llm.js";
 import { sendMail } from "./mailer.js";
 import { coerceSession, computeTotalScore, blankSession } from "../shared/cupping.js";
 import { computeMachineProfile } from "../shared/learn.js";
@@ -47,8 +48,9 @@ export function createApp({
 	db,
 	root,
 	env = process.env,
-	// Injectable so tests can stub the Pi-agent call; production always uses the real one.
+	// Injectable so tests can stub the LLM calls; production always uses the real ones.
 	evaluateRoast = defaultEvaluateRoast,
+	listModels = defaultListModels,
 } = {}) {
 	const app = express();
 	const production = env.NODE_ENV === "production";
@@ -1119,6 +1121,13 @@ export function createApp({
 		},
 	);
 
+	// Admin-chosen LLM model ("provider:id"), empty = auto. Read per call so a change takes
+	// effect immediately without restarting the app.
+	const llmModelSetting = async () =>
+		(
+			await db.query("SELECT value FROM app_settings WHERE key='llm_model'")
+		).rows[0]?.value || "";
+
 	// ─── Actual roasts (finished .alog uploads) ────────────────────────────
 	const toRoastRow = (row, { full = false } = {}) => {
 		const parsed = row.parsed || {};
@@ -1154,7 +1163,11 @@ export function createApp({
 			).rows[0];
 			if (!row) return;
 			try {
-				const evaluation = await evaluateRoast(row.parsed, row.plan ?? null);
+				const evaluation = await evaluateRoast(
+					row.parsed,
+					row.plan ?? null,
+					await llmModelSetting(),
+				);
 				await db.query(
 					"UPDATE actual_roasts SET evaluation=$1, evaluation_status='done', evaluation_error=NULL, updated_at=now() WHERE id=$2",
 					[evaluation, roastId],
@@ -1727,6 +1740,59 @@ export function createApp({
 			res.json({ ok: true, links });
 		},
 	);
+	// The LLM model picker: which configured model runs prefill and roast reviews. Listing can
+	// legitimately fail (no models configured yet) — the GET still succeeds so the admin page can
+	// say so instead of erroring, and only a non-empty PUT requires the list for validation.
+	app.get("/api/admin/llm", requireAuth, admin, async (req, res, next) => {
+		try {
+			const current = await llmModelSetting();
+			let models = [];
+			let modelsError = null;
+			try {
+				models = await listModels();
+			} catch (e) {
+				modelsError = "llm_unavailable";
+			}
+			res.json({ ok: true, current, models, modelsError });
+		} catch (e) {
+			next(e);
+		}
+	});
+	app.put(
+		"/api/admin/llm",
+		requireAuth,
+		csrf,
+		admin,
+		async (req, res, next) => {
+			try {
+				const model = req.body.model;
+				if (typeof model !== "string" || model.length > 200)
+					return res.status(400).json({ ok: false, code: "bad_request" });
+				if (model !== "") {
+					let models;
+					try {
+						models = await listModels();
+					} catch (e) {
+						return res
+							.status(503)
+							.json({ ok: false, code: "llm_unavailable" });
+					}
+					if (!models.some((m) => m.key === model))
+						return res
+							.status(400)
+							.json({ ok: false, code: "unknown_model" });
+				}
+				await db.query(
+					"UPDATE app_settings SET value=$1 WHERE key='llm_model'",
+					[model],
+				);
+				await audit(req.user.id, "llm_model_changed", model || "auto");
+				res.json({ ok: true, current: model });
+			} catch (e) {
+				next(e);
+			}
+		},
+	);
 	app.put(
 		"/api/admin/signup-enabled",
 		requireAuth,
@@ -1837,7 +1903,10 @@ export function createApp({
 				.status(400)
 				.json({ ok: false, code: "bad_url", error: "Missing url." });
 		try {
-			const result = await runPrefill(await fetchPageText(url));
+			const result = await runPrefill(
+				await fetchPageText(url),
+				await llmModelSetting(),
+			);
 			res.json({ ok: true, ...result });
 		} catch (err) {
 			const code = err.code ?? "prefill_failed";