fix(coding-agent): removed system-reminder wrapper from file context

- Sent file contents as plain text instead of wrapping in `` tags.
- Joined file entries with single newlines instead of double.

packages/coding-agent/src/session/messages.ts

@@ -564,10 +564,8 @@ export function convertToLlm(messages: AgentMessage[]): Message[] {
 							const inner = file.content ? `\n${file.content}\n` : "\n";
 							return `<file path="${file.path}">${inner}</file>`;
 						})
-						.join("\n\n");
-					const content: (TextContent | ImageContent)[] = [
-						{ type: "text" as const, text: `<system-reminder>\n${fileContents}\n</system-reminder>` },
-					];
+						.join("\n");
+					const content: (TextContent | ImageContent)[] = [{ type: "text" as const, text: fileContents }];
 					for (const file of m.files) {
 						if (file.image) {
 							content.push(file.image);