[light] Add color option to strobe and other color state (#19874)

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
Co-authored-by: J. Nick Koston <nick@home-assistant.io>

tests/components/fastled_clockless/common.yaml

@@ -21,6 +21,8 @@ light:
               green: 0%
               blue: 0%
               num_leds: 1
+            - color: darkred
+              num_leds: 1
           add_led_interval: 100ms
           reverse: false
       - addressable_scan:

tests/components/light/common.yaml

@@ -429,6 +429,10 @@ light:
               blue: 0%
               duration: 1s
               transition_length: 500ms
+            - state: true
+              color: darkred
+              duration: 1s
+              transition_length: 500ms
   - platform: partition
     id: test_addressable_transition
     name: Addressable Transition Test