feat(protection): implement multi-layered protection for feature_list.json

Introduces a comprehensive strategy to safeguard the feature_list.json file from accidental modifications. Key enhancements include:

1. **Prompt-Level Warnings**: Added explicit warnings in agent prompts to prevent direct modifications.
2. **Dedicated MCP Tool**: Implemented the UpdateFeatureStatus tool for safe feature updates.
3. **File-Level Validation & Auto-Backup**: Added validation checks and automatic backups before modifications to prevent data loss.
4. **Tool Access Control**: Restricted agent access to critical tools, ensuring only the designated MCP tool can modify the feature list.

This update significantly reduces the risk of catastrophic data loss and ensures a robust feature management process.

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

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

@@ -31,7 +31,9 @@ import {
   Minimize2,
   Square,
   Maximize2,
+  FlaskConical,
 } from "lucide-react";
+import { Checkbox } from "@/components/ui/checkbox";
 
 export function SettingsView() {
   const {
@@ -42,6 +44,8 @@ export function SettingsView() {
     setTheme,
     kanbanCardDetailLevel,
     setKanbanCardDetailLevel,
+    defaultSkipTests,
+    setDefaultSkipTests,
   } = useAppStore();
   const [anthropicKey, setAnthropicKey] = useState(apiKeys.anthropic);
   const [googleKey, setGoogleKey] = useState(apiKeys.google);
@@ -627,6 +631,49 @@ export function SettingsView() {
             </div>
           </div>
 
+          {/* Feature Defaults Section */}
+          <div className="rounded-xl border border-border bg-card backdrop-blur-md overflow-hidden">
+            <div className="p-6 border-b border-border">
+              <div className="flex items-center gap-2 mb-2">
+                <FlaskConical className="w-5 h-5 text-brand-500" />
+                <h2 className="text-lg font-semibold text-foreground">
+                  Feature Defaults
+                </h2>
+              </div>
+              <p className="text-sm text-muted-foreground">
+                Configure default settings for new features.
+              </p>
+            </div>
+            <div className="p-6 space-y-4">
+              <div className="space-y-3">
+                <div className="flex items-start space-x-3">
+                  <Checkbox
+                    id="default-skip-tests"
+                    checked={defaultSkipTests}
+                    onCheckedChange={(checked) =>
+                      setDefaultSkipTests(checked === true)
+                    }
+                    className="mt-0.5"
+                    data-testid="default-skip-tests-checkbox"
+                  />
+                  <div className="space-y-1">
+                    <Label
+                      htmlFor="default-skip-tests"
+                      className="text-foreground cursor-pointer font-medium"
+                    >
+                      Skip automated testing by default
+                    </Label>
+                    <p className="text-xs text-muted-foreground">
+                      When enabled, new features will default to manual
+                      verification instead of TDD (test-driven development).
+                      You can still override this for individual features.
+                    </p>
+                  </div>
+                </div>
+              </div>
+            </div>
+          </div>
+
           {/* Save Button */}
           <div className="flex items-center gap-4">
             <Button