[Testing Improvement] Add mapping tests for ChatMessageEntity (#693)

* 🧪 test: Add mapping tests for ChatMessageEntity to/from ChatMessage

* Added comprehensive tests to `ChatMessageMapperTest.kt` verifying the pure mappings between Room database entities (`ChatMessageEntity`) and UI models (`ChatMessage`).
* Verified fallback logics for enums (MessageRole and ToolStatus).
* Ensures regression prevention when underlying data models change.

* 🧪 test: Refactor mapper boolean assertions to assertTrue/assertFalse

* Changed assertEquals(true/false, isStreaming) to assertTrue/assertFalse
as suggested in the review.

app/src/test/java/com/m57/hermescontrol/data/local/ChatMessageMapperTest.kt

@@ -2,10 +2,117 @@ package com.m57.hermescontrol.data.local
 
 import com.m57.hermescontrol.ui.chat.ChatMessage
 import com.m57.hermescontrol.ui.chat.MessageRole
+import com.m57.hermescontrol.ui.chat.ToolStatus
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
 import org.junit.Test
 
 class ChatMessageMapperTest {
+    @Test
+    fun entityToUiModel_mapsAllPropertiesCorrectly() {
+        val entity =
+            ChatMessageEntity(
+                id = "msg-1",
+                sessionId = "session-a",
+                role = "TOOL",
+                content = "Tool output",
+                reasoningText = "Thinking",
+                timestamp = 1000L,
+                toolName = "search",
+                toolStatus = "RUNNING",
+                isStreaming = true,
+            )
+
+        val ui = entity.toUiModel()
+
+        assertEquals("msg-1", ui.id)
+        assertEquals(MessageRole.TOOL, ui.role)
+        assertEquals("Tool output", ui.content)
+        assertEquals("Thinking", ui.reasoningText)
+        assertEquals(1000L, ui.timestamp)
+        assertEquals("search", ui.toolName)
+        assertEquals(ToolStatus.RUNNING, ui.toolStatus)
+        assertTrue(ui.isStreaming)
+    }
+
+    @Test
+    fun uiModelToEntity_mapsAllPropertiesCorrectly() {
+        val ui =
+            ChatMessage(
+                id = "msg-2",
+                role = MessageRole.SYSTEM,
+                content = "System prompt",
+                reasoningText = "",
+                timestamp = 2000L,
+                toolName = null,
+                toolStatus = null,
+                isStreaming = false,
+            )
+
+        val entity = ui.toEntity("session-b")
+
+        assertEquals("msg-2", entity.id)
+        assertEquals("session-b", entity.sessionId)
+        assertEquals("SYSTEM", entity.role)
+        assertEquals("System prompt", entity.content)
+        assertEquals("", entity.reasoningText)
+        assertEquals(2000L, entity.timestamp)
+        assertNull(entity.toolName)
+        assertNull(entity.toolStatus)
+        assertFalse(entity.isStreaming)
+    }
+
+    @Test
+    fun entityToUiModel_mapsRolesCorrectly() {
+        assertEquals(MessageRole.USER, createEntityWithRole("USER").toUiModel().role)
+        assertEquals(MessageRole.ASSISTANT, createEntityWithRole("ASSISTANT").toUiModel().role)
+        assertEquals(MessageRole.SYSTEM, createEntityWithRole("SYSTEM").toUiModel().role)
+        assertEquals(MessageRole.TOOL, createEntityWithRole("TOOL").toUiModel().role)
+    }
+
+    @Test
+    fun entityToUiModel_mapsUnknownRoleToAssistant() {
+        assertEquals(MessageRole.ASSISTANT, createEntityWithRole("UNKNOWN").toUiModel().role)
+        assertEquals(MessageRole.ASSISTANT, createEntityWithRole("").toUiModel().role)
+    }
+
+    @Test
+    fun entityToUiModel_mapsToolStatusCorrectly() {
+        assertEquals(ToolStatus.RUNNING, createEntityWithToolStatus("RUNNING").toUiModel().toolStatus)
+        assertEquals(ToolStatus.COMPLETED, createEntityWithToolStatus("COMPLETED").toUiModel().toolStatus)
+        assertEquals(ToolStatus.FAILED, createEntityWithToolStatus("FAILED").toUiModel().toolStatus)
+    }
+
+    @Test
+    fun entityToUiModel_mapsUnknownToolStatusToNull() {
+        assertNull(createEntityWithToolStatus("UNKNOWN").toUiModel().toolStatus)
+        assertNull(createEntityWithToolStatus("").toUiModel().toolStatus)
+        assertNull(createEntityWithToolStatus(null).toUiModel().toolStatus)
+    }
+
+    private fun createEntityWithRole(role: String): ChatMessageEntity {
+        return ChatMessageEntity(
+            id = "id",
+            sessionId = "session",
+            role = role,
+            content = "content",
+            timestamp = 0L,
+        )
+    }
+
+    private fun createEntityWithToolStatus(status: String?): ChatMessageEntity {
+        return ChatMessageEntity(
+            id = "id",
+            sessionId = "session",
+            role = "TOOL",
+            content = "content",
+            timestamp = 0L,
+            toolStatus = status,
+        )
+    }
+
     @Test
     fun entityToUiModelCarriesReasoningText() {
         val entity =