feat: add LLM provider settings page

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/lib/api/settings.remote.ts

@@ -0,0 +1,54 @@
+import { form, query, getRequestEvent } from '$app/server';
+import { db } from '$lib/server/db';
+import { llmConfig } from '$lib/server/db/schema';
+import { eq } from 'drizzle-orm';
+import { llmConfigSchema } from '$lib/schema/settings';
+
+export const getConfig = query(async () => {
+	const { locals } = getRequestEvent();
+	if (!locals.user) return null;
+
+	const config = await db
+		.select()
+		.from(llmConfig)
+		.where(eq(llmConfig.userId, locals.user.id))
+		.limit(1);
+
+	if (config.length === 0) return null;
+
+	// mask the API key for display
+	return {
+		...config[0],
+		apiKey: config[0].apiKey.slice(0, 8) + '...' + config[0].apiKey.slice(-4)
+	};
+});
+
+export const updateConfig = form(llmConfigSchema, async (data) => {
+	const { locals } = getRequestEvent();
+	if (!locals.user) return;
+
+	const existing = await db
+		.select()
+		.from(llmConfig)
+		.where(eq(llmConfig.userId, locals.user.id))
+		.limit(1);
+
+	if (existing.length > 0) {
+		await db
+			.update(llmConfig)
+			.set({
+				provider: data.provider,
+				apiKey: data.apiKey,
+				model: data.model ?? null
+			})
+			.where(eq(llmConfig.userId, locals.user.id));
+	} else {
+		await db.insert(llmConfig).values({
+			id: crypto.randomUUID(),
+			userId: locals.user.id,
+			provider: data.provider,
+			apiKey: data.apiKey,
+			model: data.model ?? null
+		});
+	}
+});

web/src/lib/schema/settings.ts

@@ -0,0 +1,7 @@
+import { object, string, pipe, minLength, optional } from 'valibot';
+
+export const llmConfigSchema = object({
+	provider: pipe(string(), minLength(1)),
+	apiKey: pipe(string(), minLength(1)),
+	model: optional(string())
+});