Create a custom not-found edge route for next applications using the app router

[dario-piotrowicz]

This PR generates a not-found custom edge route for users creating next-on-pages applications that use the app router.

Having such route is not mandatory but it helps avoiding a gotcha that can trip people over: https://github.com/cloudflare/next-on-pages/blob/56391355c3028737a4b0069a5126ccaec24e53b1/packages/next-on-pages/docs/gotchas.md#not-found

[changeset-bot]

🦋 Changeset detected

Latest commit: cf26143

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
create-cloudflare	Minor

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7408676904/npm-package-wrangler-4625

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/7408676904/npm-package-wrangler-4625

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7408676904/npm-package-wrangler-4625 dev path/to/script.js

Additional artifacts:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7408676904/npm-package-miniflare-4625

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7408676904/npm-package-cloudflare-pages-shared-4625

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7408676904/npm-package-create-cloudflare-4625 --no-auto-update

Note that these links will no longer work once the GitHub Actions artifact expires.

---

wrangler@3.22.2 includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20231218.0
workerd	1.20231218.0	1.20231218.0
workerd --version	1.20231218.0	2023-12-18

|

Please ensure constraints are pinned, and miniflare/workerd minor versions match.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (98dee93) 75.41% compared to head (cf26143) 75.67%.
Report is 37 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4625      +/-   ##
==========================================
+ Coverage   75.41%   75.67%   +0.25%     
==========================================
  Files         242      243       +1     
  Lines       12965    13095     +130     
  Branches     3337     3375      +38     
==========================================
+ Hits         9778     9909     +131     
+ Misses       3187     3186       -1     

see 23 files with indirect coverage changes

[petebacondarwin]

Let's move the error handling out of probePaths().

[petebacondarwin]

Cool!