[null and void]

Could the shock-wave have triggered planetary formation?

[Darksheare]

Possibly.
But it could also force the clearing of accretionary materials.

[SunkenCiv]

Or, the material out of which they were made could have arrived that way, being ex- of the supernova. There’s a link above to the “iron sun” topic and the underlying article (which isn’t linked at the topic, oddly) which suggests another scenario, which is that our Sun is itself the leftovers of the earlier star.