Does applying for permanent residence hurt my chances of getting a visitor visa approved?

Not automatically. Dual intent exists specifically so that having a permanent residence application in progress does not, by itself, defeat a temporary resident application like a visitor visa. An officer is not permitted to refuse simply because you also want to immigrate eventually, and a pending PR application should not, on its own, be treated as proof you will not leave Canada if it does not succeed.

That said, the officer still needs to be satisfied you would genuinely leave Canada if your temporary stay ends without the permanent residence application succeeding, so other factors continue to matter just as much as they would for any visitor visa application. Weak ties to your home country, an unclear travel history, or no credible explanation of your plans if the PR application does not succeed can still lead to a refusal, regardless of dual intent.

The practical takeaway is that the existence of a PR application should not be hidden or downplayed, but the rest of the application still needs to make a genuine, credible case that you would comply with the temporary conditions either way.