Clean up code. Reorganize files. Port stuff from other branches. + more

This turns the project into a monorepo using pnpm workspaces,
dramatically simplifying the build process. It also fixes a lot of bugs
and just generally makes the codebase a lot cleaner.

example-app/server/api/pow/challenge.post.ts

@@ -13,26 +13,29 @@ export default defineEventHandler(async (event) => {
     const body = await readValidatedBody(event, challengeSchema.safeParse);
 
     if (!body.success) {
+        const errors = z.treeifyError(body.error);
+        const error_message = Object.entries(errors.errors).map(([key, value]) => `${key}: ${value}`).join('\n');
+
         throw createError({
             statusCode: 400,
-            statusMessage: 'Validation failed'
+            statusMessage: error_message
         })
     }
 
-    let target = body.data.challenge;
-    let nonce = body.data.nonce;
+    let { challenge, nonce } = body.data;
+
+    const outstanding_challenge = outstandingChallenges.get(body.data.challenge)!;
+    // always delete the challenge on a solve attempt
+    clearTimeout(outstanding_challenge.timeout);
+    outstandingChallenges.delete(challenge);
 
     // check if the challenge is valid
-    let challenge_valid = await validate_challenge(outstandingChallenges.get(target)!.challenge, {
-        challenge: target,
-        nonce: nonce
+    let challenge_valid = await validate_challenge(outstandingChallenges.get(challenge)!.challenge, {
+        challenge,
+        nonce,
     });
 
     if (challenge_valid) {
-        // clear the challenge
-        clearTimeout(outstandingChallenges.get(target)!.timeout);
-        outstandingChallenges.delete(target);
-
         return {
             message: 'Challenge solved'
         };