* sys/pprof: add pprof routes to the system backend
* sys/pprof: add pprof paths to handler with local-only check
* fix trailing slash on pprof index endpoint
* use new no-forward handler on pprof
* go mod tidy
* add pprof external tests
* disallow streaming requests to exceed DefaultMaxRequestDuration
* add max request duration test
Calvin Leung Huang