Scan addresses when importing seed phrase upto nth index

It would be great if metamask tried to scan upto 20 addresses when importing from seed phrase.
If last 6 addresses are empty, but first 14 are not, add all those accounts automatically.

OR add ability to specify an index until which I would like to create my accounts(Some sort of advanced option when I'm importing a seed phrase)

No files, tests, or entry points are identified in the issue. Start by locating the seed phrase import flow and determine whether the implementation should scan up to 20 addresses or expose a configurable account index; done means non-empty accounts are added automatically as described.

Written by the indexing model from the issue text.