Upgrade TypeScript, Svelte, and related packages to latest

[chrispcampbell]

After upgrading to VS Code 1.77.3 a few months back (which included TypeScript 5 support), our tsconfig.json files are now being highlighted in red due to some tsconfig properties that were deprecated in TS 5.0.

The new replacement for importsNotUsedAsValues is verbatimModuleSyntax:
https://devblogs.microsoft.com/typescript/announcing-typescript-5-0/#verbatimmodulesyntax
microsoft/TypeScript#52203
https://typescript-eslint.io/rules/consistent-type-imports/

We should upgrade to the latest TypeScript and update the tsconfig.json files (and our ESLint settings) to make this problem go away.

Some additional notes from when I went through a similar upgrade for En-ROADS a couple months ago:

This was supposed to be a simple change to some tsconfig files, but as is typical for a TypeScript upgrade, it prompted upgrades for other related packages. Our older version of svelte-check is not compatible with TS 5, so I upgraded that, but the latest svelte-check requires a newer version of svelte, so I upgraded that as well. Also had to upgrade to the latest version of eslint and related packages.

The upgrade to svelte-check causes many new a11y warnings that I've had to silence for the time being.

I will also need to upgrade typedoc to the latest version, since the one we had pinned earlier didn't fully support TS 5.