chore: add sourceMaps to dev-builds

[SgtPooki]

• npm run dev-build produces sourceMaps.

╰─ ✔ ❯ npm run dev-build
╰─ ✔ ❯ ls add-on/dist/**/*.js.map | wc -l
       8

• npm run build does not produce sourceMaps.

╰─ ✔ ❯ npm run build
╰─ ✔ ❯ ls add-on/dist/**/*.js.map | wc -l
zsh: no matches found: add-on/dist/**/*.js.map
       0