chore: pin Heroku stack to heroku-24 in app.json

[claude]

Requested by John Kleinschmidt · Slack thread

Before: app.json does not declare a Heroku stack, so a re-created app would land on the account default (the live app is currently on Heroku-22, which Heroku deprecates on 2026-11-01).

After: app.json pins "stack": "heroku-24", so heroku create / the Deploy button produce an app on the current stack.

This only affects newly created apps. The live app's stack is changed separately with heroku stack:set heroku-24 -a electron-roller followed by a deploy.

🤖 Generated with Claude Code

https://claude.ai/code/session_01KPY7eE3LVy1sVRSQGkR94d

---

Generated by Claude Code

[claude]

Looks good, straightforward config change.

What was reviewed: the one-line addition of "stack": "heroku-24" to app.json — confirmed it's valid JSON and a recognized Heroku app.json field, placed correctly between addons and buildpacks. No code, build, or deployment logic is modified; this only affects the stack used when new apps are created via the Deploy button or heroku create.

Extended reasoning...

Overview

The only change is a single added key-value pair, "stack": "heroku-24", inserted into app.json between the existing addons array and buildpacks section. app.json is a Heroku manifest file used for defining app configuration for "Deploy to Heroku" buttons and heroku create from a manifest; stack is a standard, documented field for this file.

Security risks

None. This is a static configuration value (a Heroku stack name/image identifier), not user input, executable code, or a secret. It has no bearing on auth, crypto, or permissions.

Level of scrutiny

Minimal. This is a one-line, additive, non-breaking config change to a declarative manifest file, with no ambiguity in intent and no ripple effects into application code. It matches exactly the kind of mechanical config tweak that warrants direct approval.

Other factors

The PR description's stated rationale (heroku-22 deprecation, migrating newly-created apps to heroku-24) is consistent with the diff; the described separate heroku stack:set step for the live app is out of scope for this file change and not something to verify here. No CODEOWNERS file was found restricting this path, no CLAUDE.md conventions apply, and there is no prior review history or outstanding objections to consider.