feat: restructure feature management and update project files

- Introduced a new `package-lock.json` to manage dependencies.
- Removed obsolete `.automaker/feature_list.json` and replaced it with a new structure under `.automaker/features/{id}/feature.json` for better organization.
- Updated various components to utilize the new features API for managing features, including creation, updates, and deletions.
- Enhanced the UI to reflect changes in feature management, including updates to the sidebar and board view.
- Improved documentation and comments throughout the codebase to clarify the new feature management process.

app/src/components/views/agent-view.tsx

@@ -594,11 +594,11 @@ export function AgentView() {
                   className={cn(
                     "max-w-[80%]",
                     message.role === "user"
-                      ? "bg-primary text-primary-foreground"
+                      ? "bg-transparent border border-primary text-foreground"
                       : "border-l-4 border-primary bg-card"
                   )}
                 >
-                  <CardContent className="p-3">
+                  <CardContent className="px-3 py-2">
                     {message.role === "assistant" ? (
                       <Markdown className="text-sm text-primary prose-headings:text-primary prose-strong:text-primary prose-code:text-primary">
                         {message.content}
@@ -610,9 +610,9 @@ export function AgentView() {
                     )}
                     <p
                       className={cn(
-                        "text-xs mt-2",
+                        "text-xs mt-1",
                         message.role === "user"
-                          ? "text-primary-foreground/70"
+                          ? "text-muted-foreground"
                           : "text-primary/70"
                       )}
                     >