nessa: retire the API copy now served by nessa-api.freno.me

The Nessa API (nessaDb.*, nessa.community.*, Clerk auth and the Clerk user
webhook) lives in the Nessa repo's server/ on pan. This copy never served
the app: RemoteAPIClient wraps every input in {"input": …}, which the stock
tRPC adapter here reads as the input itself (queries 404, writes no-op).
Clerk's webhook already targets nessa-api.freno.me.

Drops the routers, nessa-auth, the webhook, NessaConnectionFactory, the
NESSA_* env and the now-unused @clerk/backend and svix. Nessa's marketing,
privacy and deletion pages stay.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/routes/api/clerk-webhook.ts

@@ -1,52 +0,0 @@
-import type { APIEvent } from "@solidjs/start/server";
-import { env } from "~/env/server";
-import { NessaConnectionFactory } from "~/server/database";
-import { handleClerkUserWebhook } from "~/server/clerk-user-webhook";
-
-function json(status: number, body: unknown): Response {
-  return new Response(JSON.stringify(body), {
-    status,
-    headers: { "Content-Type": "application/json" }
-  });
-}
-
-/**
- * Clerk webhook endpoint — receives `user.created` / `user.updated` events.
- *
- * Configure the endpoint URL in the Clerk Dashboard → Webhooks
- * (e.g. https://freno.me/api/clerk-webhook in prod, or an ngrok/dev url for
- * local dev). The signing secret (`whsec_...`) is stored in
- * `NESSA_CLERK_WEBHOOK_SECRET` and used to verify each request via Svix.
- *
- * The raw body is read verbatim from the inflight request so the Svix
- * signature is computed over the exact bytes Clerk sent.
- */
-export async function POST(event: APIEvent) {
-  const svixId = event.request.headers.get("svix-id");
-  const svixTimestamp = event.request.headers.get("svix-timestamp");
-  const svixSignature = event.request.headers.get("svix-signature");
-
-  if (!svixId || !svixTimestamp || !svixSignature) {
-    return json(400, { error: "Missing Svix signature headers" });
-  }
-
-  let rawBody: string;
-  try {
-    rawBody = await event.request.text();
-  } catch {
-    return json(400, { error: "Missing request body" });
-  }
-
-  const result = await handleClerkUserWebhook({
-    rawBody,
-    headers: {
-      "svix-id": svixId,
-      "svix-timestamp": svixTimestamp,
-      "svix-signature": svixSignature
-    },
-    webhookSecret: env.NESSA_CLERK_WEBHOOK_SECRET,
-    conn: NessaConnectionFactory()
-  });
-
-  return json(result.status, result.body);
-}