Who pays for the work permit, and what happens to it when the employee gets fired?


From last December, I started working for a French startup in Paris, and they organized for my work permit called carte séjour pluriannuelle-passport talent salarié qualifié. I was supposed to pick it up March 7, but today I got fired from the same company.

I’d like to ask two questions:

  1. Who pays the tax (269€) for the above work permit? The company obviously won’t pay, so can I pay for it out of my own pocket?
  2. My contract will show that I’m employed under the same company until March 15, as they’re supposed to keep the employee under payroll for two more weeks, if (s)he’s fired within the trial period. So, am I still legally allowed to pick up the above work permit? My point is, I’m still employed when I’m picking up the work permit, but I’ve the knowledge that it’ll end after a week.
  3. Once my contract ends, is my work permit still valid and does it still serve as a work/residence permit for any other company, or will it have to arrange a new permit?
  4. Once my contract ends March 15 and if I don’t get a new job by then, do I’ve to ask for a new residence permit?

Thank you very much!