A residence permit or visa stays valid as long as it isn't rescinded. There is no obligation for you to leave the French territory immediately, that much is clear. At the same time, I don't really know how likely the préfecture is to move to rescind it and how fast. It could also be possible to stay for some time and look for another job as long as you are getting unemployment benefits but if you just moved to Paris, you might not have worked long enough to get any.
You also wrote that your carte de séjour is “being manufactured”. What's your basis for that? Applying for a permit is not a mere formality. Even if you already had to submit a lot of information to get a visa, legally your situation is being evaluated anew (I am assuming you are currently staying under the long-stay visa you needed to move to Paris). In my experience, it is rare to get any insights into what a decision might be ahead of the appointment to receive it. Until you have got your residence permit in hand, it could still be refused.
If the permit is refused, you would receive a letter informing you of this (or even be given that letter in person when you show up to your appointment at the préfecture) and it will probably come with what's called an obligation de quitter le territoire français (OQTF). From that point on, you have 30 days to leave (there are other variants like an OQTF sans délai but that's unlikely in your case).
It is not forbidden to change employers (i.e. you don't need to leave France to reapply) but your new employer will have to sponsor you again and you will have to submit a new application. That's more likely to work if you find a similar job (one that would qualify for a passeport talent on its own merits), you cannot take any job to make ends meet for now (that becomes possible after some time).