feat: message-per-row transcript, session resume, drop the composer (#4)

src/lib/types.ts

@@ -85,3 +85,23 @@ export interface ModelInfo {
   name: string;
   parameterSize?: string;
 }
+
+/**
+ * One rendered line of the conversation.
+ *
+ * A turn is stored as a question/answer pair, but the transcript is displayed as
+ * a flat sequence of messages so each side can carry its own icon and weight.
+ */
+export interface ThreadMessage {
+  id: string;
+  role: "user" | "assistant";
+  /** Full text, used for the detail panel and for copying. */
+  text: string;
+  /** Single-line text for the list row, because rows are one line tall. */
+  preview: string;
+  createdAt: number;
+  isStreaming: boolean;
+  thinking: string;
+  toolCalls: ToolCallRecord[];
+  error?: string;
+}