Fix Prettier formatting regression and Astro type-check errors

`Render Modal as real markup` (#2742) reformatted ~140 files back to
tabs/semicolons, breaking the Prettier config added by the Astro
quality gates (#2749). Re-run prettier --write to restore it, and fix
the type errors it had been masking: HTMLElement casts and `this`
typing in ChangePasswordModalContent/ConfirmDeleteModalContent
scripts, plain-JS syntax in the inline-injected progress.astro script,
narrowed prop unions in Button/Check/Spinner, nullable icon svg casts
in Icons/Rating, and a duplicate firstLetters/invalid `placeholder`
attribute in Select.astro. Also fix shared/vitest.config.mts's stale
`astro/lib/**/*.test.ts` include glob left over from the shared source
restructure, which made `pnpm test` report zero test files.

shared/ui/Select.astro

@@ -45,8 +45,6 @@ const selectClass = [
 
 const isMultiple = Boolean(multiple || data.multiple);
 
-const firstLetters = (s: string) => (s || '').split(' ').map((w) => w.charAt(0)).join('');
-
 interface Person {
 	id: string;
 	full_name: string;
@@ -95,7 +93,7 @@ const selectId = id ? `select-${id}` : undefined;
 	id && (
 		<select
 			class:list={selectClass}
-			placeholder={placeholder}
+			data-placeholder={placeholder}
 			id={`select-${id}`}
 			value={value}
 			multiple={isMultiple ? '' : undefined}