Is your feature request related to a problem? Please describe.
It is always painful to freshly mark everything you've ever enjoyed. The current data importers are quite limited, which I believe prevents many people from migrating to here. Douban can be a source but not all gamers keep a habit of using it and it primarily caters to Chinese users.

Describe the solution you'd like
I am proposing adding an importer for Steam utilizing their web API and is currently working on a PR. The planned features include

• Let users supply their own steam userid and api key from https://steamcommunity.com/dev/apikey
• read owned games, estimate the shelf type + created time of mark from last played time and total play time
• read wishlist, and add as ShelfType.WISHLIST

Support for other platforms like Epic, GOG, and Itch.io could also be explored, though I’m less familiar with them.

Describe alternatives you've considered
Open to suggestions if there are any viable alternatives.

Additional context
None.