Fix 404 error when user creates devlog with error and reloads

[alaninnovates]

When a user creates a new devlog with an error and reloads the page, the route will not 404 anymore.
Current behavior:

• User submits the devlog creation form with an error, posts to the url /projects/:project_id/devlogs
• Server renders :new, but the url (without the /new) is changed. This leads to a 404 error on reload

Fixed behavior:

• User submits the devlog creation form with an error, posts to the url /projects/:project_id/devlogs/new
• Server renders :new, the url is preserved (with the /new) and there is no 404 error

The rationale for using the alias paths is that this allows the devlog text to be preserved on error, instead of clearing it with a redirect.

Video Demo
https://hackclub.enterprise.slack.com/files/U07B27ZHEJU/F0A5Q0FM2SX/screen_recording_2025-12-28_at_4.28.54___pm.mov

Resolves this Slack #flavortown-help ticket: https://hackclub.slack.com/archives/C09MATKQM8C/p1766465463434559
Additional details to this decision available in the thread

[maxwofford]

interesting. i'm still a little confused why we need to change the routes & not just update the forms to handle this?

[alaninnovates]

How would the form be updated to handle this? Sorry, newbie to rails here. The route I explored was making the create handler in the controller redirect to the /new page, but this would lead to the devlog text being lost. I'm not familiar, what other options are there? Thanks!