feat(#525): render reasoning.delta / reasoning.available stream (#543)

* feat(#525): add ReasoningDelta + ReasoningAvailable WsEvent types

* feat(#525): parse reasoning.delta + reasoning.available; route through reducer + StreamingState

* feat(#525): add reasoning streaming buffer to ChatStreamingController

* feat(#525): dispatch ReasoningDelta/ReasoningAvailable in ChatViewModel

* feat(#525): render collapsible ReasoningIndicator in chat list

* fix(#525): address review — icons+semantics, LocalHermesStatusColors, drop redundant ReasoningAvailable branch

* feat(#525): persist reasoningText on model, entity, mapper + Room migration 3->4

* feat(#525): reducer + streaming carry reasoningText onto message

* feat(#525): render persisted reasoning above each assistant bubble, drop global indicator

* nix: flake

* nix: flake

---------

Co-authored-by: M57 <m57@hermes-control.app>

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

@@ -0,0 +1,59 @@
+package com.m57.hermescontrol.data.local
+
+import com.m57.hermescontrol.ui.chat.ChatMessage
+import com.m57.hermescontrol.ui.chat.MessageRole
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class ChatMessageMapperTest {
+    @Test
+    fun entityToUiModelCarriesReasoningText() {
+        val entity =
+            ChatMessageEntity(
+                id = "msg-1",
+                sessionId = "session-a",
+                role = "assistant",
+                content = "Answer",
+                reasoningText = "Let me think step by step",
+                timestamp = 1000L,
+            )
+
+        val ui = entity.toUiModel()
+
+        assertEquals("Let me think step by step", ui.reasoningText)
+        assertEquals("Answer", ui.content)
+    }
+
+    @Test
+    fun uiModelToEntityCarriesReasoningText() {
+        val ui =
+            ChatMessage(
+                id = "msg-2",
+                role = MessageRole.ASSISTANT,
+                content = "Answer",
+                reasoningText = "Chain of thought",
+                timestamp = 2000L,
+            )
+
+        val entity = ui.toEntity("session-b")
+
+        assertEquals("Chain of thought", entity.reasoningText)
+        assertEquals("session-b", entity.sessionId)
+    }
+
+    @Test
+    fun roundTripPreservesReasoningText() {
+        val ui =
+            ChatMessage(
+                id = "msg-3",
+                role = MessageRole.ASSISTANT,
+                content = "Answer",
+                reasoningText = "r",
+                timestamp = 3000L,
+            )
+
+        val roundTripped = ui.toEntity("s").toUiModel()
+
+        assertEquals("r", roundTripped.reasoningText)
+    }
+}