feat: refactor spec-view to folder pattern and add feature count selector

Closes #151

- Refactor spec-view.tsx from 1,230 lines to ~170 lines following folder-pattern.md
- Create unified CreateSpecDialog with all features from both dialogs:
  - featureCount selector (20/50/100) - was missing in spec-view
  - analyzeProject checkbox - was missing in sidebar
- Extract components: spec-header, spec-editor, spec-empty-state
- Extract hooks: use-spec-loading, use-spec-save, use-spec-generation
- Extract dialogs: create-spec-dialog, regenerate-spec-dialog
- Update sidebar to use new CreateSpecDialog with analyzeProject state
- Delete deprecated project-setup-dialog.tsx

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/ui/src/components/views/spec-view/hooks/use-spec-loading.ts

@@ -0,0 +1,46 @@
+import { useEffect, useState, useCallback } from "react";
+import { useAppStore } from "@/store/app-store";
+import { getElectronAPI } from "@/lib/electron";
+
+export function useSpecLoading() {
+  const { currentProject, setAppSpec } = useAppStore();
+  const [isLoading, setIsLoading] = useState(true);
+  const [specExists, setSpecExists] = useState(true);
+
+  const loadSpec = useCallback(async () => {
+    if (!currentProject) return;
+
+    setIsLoading(true);
+    try {
+      const api = getElectronAPI();
+      const result = await api.readFile(
+        `${currentProject.path}/.automaker/app_spec.txt`
+      );
+
+      if (result.success && result.content) {
+        setAppSpec(result.content);
+        setSpecExists(true);
+      } else {
+        // File doesn't exist
+        setAppSpec("");
+        setSpecExists(false);
+      }
+    } catch (error) {
+      console.error("Failed to load spec:", error);
+      setSpecExists(false);
+    } finally {
+      setIsLoading(false);
+    }
+  }, [currentProject, setAppSpec]);
+
+  useEffect(() => {
+    loadSpec();
+  }, [loadSpec]);
+
+  return {
+    isLoading,
+    specExists,
+    setSpecExists,
+    loadSpec,
+  };
+}