hey Pardhu, It’s been a year or two since I did this, but I can share what (I think) I know.
Terminology wise I think you need a ‘Pesidence Permit’ type -> Working.
To get these instead of Visas, you need a ‘foreign experts certificate’ mine looked like another passport, then with this I think you apply for the residence permit.
Because there seems to be many foreign architects in town, I guess this is an industry (along with IT) that you can get a foreign experts certificate.
In my case my company arranged it all, so really try to push yours to, I guess the information is there somewhere for businesses to use foreigners this way. if you live/work in the new development zone maybe the local PSB can instruct. or the central PSB.
A gotcha I can think of: if you’re on a visa, maybe you’re not supposed to not be paid/on a local contract. if it comes to light as part of this process you have been. things might be bad. and they seem to be more strict than usual at the moment.