Depends on what's on the HOA's permitted tree list. Also, it's not just the fires, but winds also. Breakage in high winds can be dangerous.
When we moved in the previous owner had Tipu trees in the back yard. They grow like weeds. Big, good for shade, but can also drop leaves like no other SoCal friendly tree. Our neighbors kept their Tipus and are now, 20 years later, close to 70 ft high We replaced a builder original tree out front and put in a Ginkgo, also a fast growing tree. Come winter be ready for yellow leaves everywhere! Thankfully the Ginkgo drops all of their leaves in about 10 days.
There are some Apple varieties that grow in OC. These can be fairly nice shade trees with bonus fruit in a couple of years. Not all that difficult of a tree to grow. If you're considering a fruit tree, I'd also recommend 2-3 Avocado trees. They grow well and can be considered a shade tree in time.
My .02c