Is providing link to my (8 pages) proof of P=NP and asking to check my proof appropriate for a math.SE question?
No, I'm not sure any stackexchange website would be considered appropriate for your "proof".
P = NP is considered an unsolved problem, "The problem has been called the most important open [unknown] problem in computer science." Some of the brightest minds and PhD's in math and computer science have attempted to prove or P = NP without success. Either your proof has a mistake, which is most likely, or you will get the equivalent of a Nobel prize in Computer Science, which is extremely unlikely. https://en.wikipedia.org/wiki/P_versus_NP_problem
At the very least consider phrasing your question- "Where is the mistake in my proof?"