…nt, tangents for array

We add `-Lo` to print verbose build logs so that errors [here](https://github.com/EliCDavis/polyform/actions/runs/16831757233/job/47680959627#step:5:214) will display the actual hash mismatch error [log](https://github.com/EliCDavis/polyform/actions/runs/16832252332/job/47682633319#step:5:214) so we know which to update.

Adds two small [Nix Flake App](https://nix.dev/manual/nix/2.28/command-ref/new-cli/nix3-run.html#apps) scripts to both document how to update sri files or clear Github Action cache, as well as make them easy to re-run.
Tried to find a way to make SRI updates runnable without nix, but since both utilties are fairly bespoke programs to fetch/install, it seemed easier to just keep it in a derivation to be run with WSL or a linux container.