feat: Allow user-agent based conditions (#1821)

* Closes #1819

src/config/types.ts

@@ -726,6 +726,25 @@ const keyConditionSchema = z.object({
   alt: z.boolean().optional(),
   meta: z.boolean().optional(),
 });
+const userAgentConditionSchema = z.object({
+  condition: z.literal('user_agent'),
+  user_agent: z.string().optional(),
+  user_agent_re: z
+    .string()
+    .refine(
+      (val) => {
+        try {
+          new RegExp(val);
+        } catch {
+          return false;
+        }
+        return true;
+      },
+      { message: 'Invalid regular expression' },
+    )
+    .optional(),
+  companion: z.boolean().optional(),
+});
 
 export const frigateCardConditionSchema = z.discriminatedUnion('condition', [
   // Stock conditions:
@@ -745,6 +764,7 @@ export const frigateCardConditionSchema = z.discriminatedUnion('condition', [
   interactionConditionSchema,
   microphoneConditionSchema,
   keyConditionSchema,
+  userAgentConditionSchema,
 ]);
 export type FrigateCardCondition = z.infer<typeof frigateCardConditionSchema>;