fix: sourceUrl опциональный (воркер сам строит URL из itemId)

src/main/kotlin/pw/binom/mirror/api/dto/CreateMirrorRequest.kt

@@ -7,7 +7,6 @@ import kotlinx.serialization.Serializable
 data class CreateMirrorRequest(
     @field:NotBlank(message = "itemId must not be blank")
     val itemId: String,
-    @field:NotBlank(message = "sourceUrl must not be blank")
-    val sourceUrl: String,
+    val sourceUrl: String = "",
     val sourceType: String = "jellyfin",
 )

src/test/kotlin/pw/binom/mirror/api/controller/MirrorControllerTest.kt

@@ -83,6 +83,21 @@ class MirrorControllerTest : AbstractIntegrationTest() {
         assertEquals(1, count)
     }
 
+    @Test
+    fun `POST mirror without sourceUrl creates a job`() {
+        mockMvc.perform(
+            post("/api/mirror")
+                .contentType(MediaType.APPLICATION_JSON)
+                .content("""{"itemId":"no-url-id"}"""),
+        ).andExpect(status().isCreated)
+
+        val response = json.decodeFromString<ByItemResponse>(
+            bodyOf(mockMvc.perform(get("/api/mirror/by-item/no-url-id")).andExpect(status().isOk).andReturn()),
+        )
+        assertEquals("no-url-id", response.itemId)
+        assertEquals("new", response.status)
+    }
+
     @Test
     fun `POST mirror returns 400 on blank itemId`() {
         postCreate("", "https://source.example/stream")