perf(app): Backport "only recreate the webpack conf when absolutely necessary" from Qv2
perf(app): Backport "only recreate the webpack conf when absolutely necessary" from Qv2

pdanpdan/quasar,quasarframework/quasar,pdanpdan/quasar,rstoenescu/quasar-framework,pdanpdan/quasar,pdanpdan/quasar,rstoenescu/quasar-framework,quasarframework/quasar,rstoenescu/quasar-framework,quasarframework/quasar,quasarframework/quasar