fix: add locked image state + qr deletion + other misc fixes

[jasukej]

Reason

• after syncing w erping + engagement reqs: stamps should be hackathon-specific (also makes url generation more consistent as we can directly sub in hackathon slug)
• delete QR if isQRUnlockable toggled off
• allow admin to add locked image state (what the hacker sees before the stamp is unlocked)

[github-actions]

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[jasukej]

I lowkey just copied over image select, as of right now don't think it's worth refactoring to its own component

[tdanielles]

functionality lgtm i think tyyyy! one thing i wanna confirm is it looks like on stamp creation only the stamp image is required but the locked image is optional. is it the case that if no one uploads anything there it would default to the locked one we have now?? just wanted to make sure it doesnt error / glitch out or anything if that happens on portal side

[jasukej]

functionality lgtm i think tyyyy! one thing i wanna confirm is it looks like on stamp creation only the stamp image is required but the locked image is optional. is it the case that if no one uploads anything there it would default to the locked one we have now?? just wanted to make sure it doesnt error / glitch out or anything if that happens on portal side

Yep on portal it will default to the one we have rn, kept it as optional for now as we backfill the stamps.

Until I merge this PR on portal it won't use the locked stamps image put I can push that change to dev separately if needed: nwplus/portal-v2#42