chore: add OpenAI gpt-5.4-mini and gpt-5.4-nano models (#6028)

chore: add OpenAI gpt-5.4-mini and gpt-5.4-nano models to ChatOpenAI model list

Add gpt-5.4-mini and gpt-5.4-nano to the OpenAI models registry with
their correct pricing:
- gpt-5.4-mini: $0.75/MTok input, $4.50/MTok output
- gpt-5.4-nano: $0.20/MTok input, $1.25/MTok output

Author: AsharibAli

packages/components/models.json

@@ -1245,6 +1245,18 @@
                     "input_cost": 0.00003,
                     "output_cost": 0.00018
                 },
+                {
+                    "label": "gpt-5.4-mini",
+                    "name": "gpt-5.4-mini",
+                    "input_cost": 0.00000075,
+                    "output_cost": 0.0000045
+                },
+                {
+                    "label": "gpt-5.4-nano",
+                    "name": "gpt-5.4-nano",
+                    "input_cost": 0.0000002,
+                    "output_cost": 0.00000125
+                },
                 {
                     "label": "gpt-5.2",
                     "name": "gpt-5.2",