Missing property in type from ActionData

Describe the bug

This is to reopen issue #6823

First of all, thanks everyone for helping with this issue, but even after upgrading to the newest sveltekit version, the bug still persists. I have updated the example repo for clearer demonstration of the bug: https://github.com/harrylaulau/sveltekittest

First issue is that when one property exist in one invalid() but not another, the type of return object with that property does not exist.

Second issue is when a property is of object type, it seems to override all other type

+page.server.ts

import { invalid, redirect } from '@sveltejs/kit';
import type { Actions } from './$types';
export const actions: Actions = {
	default: async ({ request, url }) => {
		if (url.searchParams.get('v') === '0') return invalid(400, { common: '1' });
		if (url.searchParams.get('v') === '1') return invalid(400, { common: '2', something: '' });

		if (url.searchParams.get('v') === '2') return invalid(400, { common2: 1 });
		if (url.searchParams.get('v') === '3') return invalid(400, { common2: '1' });
		if (url.searchParams.get('v') === '4') return invalid(400, { common2: {} });
	}
};

+page.svelte

1. return type with something does not exist
2. return type with common2 having the string type or a number type does not exist

Reproduction

https://github.com/harrylaulau/sveltekittest

Logs

No response

System Info

System:
    OS: macOS 12.6
    CPU: (10) arm64 Apple M1 Max
    Memory: 7.60 GB / 32.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 16.15.0 - ~/.nvm/versions/node/v16.15.0/bin/node
    Yarn: 1.22.19 - ~/Library/pnpm/yarn
    npm: 8.12.1 - ~/.nvm/versions/node/v16.15.0/bin/npm
    Watchman: 2022.09.12.00 - /opt/homebrew/bin/watchman
  Browsers:
    Chrome: 105.0.5195.125
    Safari: 16.0
  npmPackages:
    @sveltejs/adapter-auto: next => 1.0.0-next.80 
    @sveltejs/kit: next => 1.0.0-next.502 
    svelte: ^3.44.0 => 3.50.1 
    vite: ^3.1.0 => 3.1.3

Severity

serious, but I can work around it

Additional Information

No response

Start with the linked reproduction and compare the generated types used by +page.server.ts and +page.svelte when invalid() returns different properties and value types. Trace how ActionData is produced and verify that the completed types retain something, common2, and their string, number, and object variants.