added fast apply

if isEdit === true & Morph API Key is in .env:
- Morph Fast Apply is activated.

app/api/apply-ai-code/route.ts

@@ -1,4 +1,5 @@
 import { NextRequest, NextResponse } from 'next/server';
+import { parseMorphEdits, applyMorphEditToFile } from '@/lib/morph-fast-apply';
 import type { SandboxState } from '@/types/sandbox';
 import type { ConversationState } from '@/types/conversation';
 
@@ -144,6 +145,12 @@ export async function POST(request: NextRequest) {
     
     // Parse the AI response
     const parsed = parseAIResponse(response);
+    const morphEnabled = Boolean(isEdit && process.env.MORPH_API_KEY);
+    const morphEdits = morphEnabled ? parseMorphEdits(response) : [];
+    console.log('[apply-ai-code] Morph Fast Apply mode:', morphEnabled);
+    if (morphEnabled) {
+      console.log('[apply-ai-code] Morph edits found:', morphEdits.length);
+    }
     
     // Initialize existingFiles if not already
     if (!global.existingFiles) {
@@ -172,6 +179,14 @@ export async function POST(request: NextRequest) {
     console.log('[apply-ai-code] Is edit mode:', isEdit);
     console.log('[apply-ai-code] Files to write:', parsed.files.map(f => f.path));
     console.log('[apply-ai-code] Existing files:', Array.from(global.existingFiles));
+    if (morphEnabled) {
+      console.log('[apply-ai-code] Morph Fast Apply enabled');
+      if (morphEdits.length > 0) {
+        console.log('[apply-ai-code] Parsed Morph edits:', morphEdits.map(e => e.targetFile));
+      } else {
+        console.log('[apply-ai-code] No <edit> blocks found in response');
+      }
+    }
     
     const results = {
       filesCreated: [] as string[],
@@ -296,9 +311,46 @@ export async function POST(request: NextRequest) {
       }
     }
     
+    // Attempt Morph Fast Apply for edits before file creation
+    const morphUpdatedPaths = new Set<string>();
+
+    if (morphEnabled && morphEdits.length > 0) {
+      if (!global.activeSandbox) {
+        console.warn('[apply-ai-code] Morph edits found but no active sandbox; skipping Morph application');
+      } else {
+        console.log(`[apply-ai-code] Applying ${morphEdits.length} fast edits via Morph...`);
+        for (const edit of morphEdits) {
+          try {
+            const result = await applyMorphEditToFile({
+              sandbox: global.activeSandbox,
+              targetPath: edit.targetFile,
+              instructions: edit.instructions,
+              updateSnippet: edit.update
+            });
+
+            if (result.success && result.normalizedPath) {
+              morphUpdatedPaths.add(result.normalizedPath);
+              results.filesUpdated.push(result.normalizedPath);
+              console.log('[apply-ai-code] Morph applied to', result.normalizedPath);
+            } else {
+              const msg = result.error || 'Unknown Morph error';
+              console.error('[apply-ai-code] Morph apply failed:', msg);
+              results.errors.push(`Morph apply failed for ${edit.targetFile}: ${msg}`);
+            }
+          } catch (e) {
+            console.error('[apply-ai-code] Morph apply exception:', e);
+            results.errors.push(`Morph apply exception for ${edit.targetFile}: ${(e as Error).message}`);
+          }
+        }
+      }
+    }
+    if (morphEnabled && morphEdits.length === 0) {
+      console.warn('[apply-ai-code] Morph enabled but no <edit> blocks found; falling back to full-file flow');
+    }
+
     // Filter out config files that shouldn't be created
     const configFiles = ['tailwind.config.js', 'vite.config.js', 'package.json', 'package-lock.json', 'tsconfig.json', 'postcss.config.js'];
-    const filteredFiles = parsed.files.filter(file => {
+    let filteredFiles = parsed.files.filter(file => {
       const fileName = file.path.split('/').pop() || '';
       if (configFiles.includes(fileName)) {
         console.warn(`[apply-ai-code] Skipping config file: ${file.path} - already exists in template`);
@@ -306,6 +358,21 @@ export async function POST(request: NextRequest) {
       }
       return true;
     });
+
+    // Avoid overwriting files already updated by Morph
+    if (morphUpdatedPaths.size > 0) {
+      filteredFiles = filteredFiles.filter(file => {
+        let normalizedPath = file.path.startsWith('/') ? file.path.slice(1) : file.path;
+        const fileName = normalizedPath.split('/').pop() || '';
+        if (!normalizedPath.startsWith('src/') &&
+            !normalizedPath.startsWith('public/') &&
+            normalizedPath !== 'index.html' &&
+            !configFiles.includes(fileName)) {
+          normalizedPath = 'src/' + normalizedPath;
+        }
+        return !morphUpdatedPaths.has(normalizedPath);
+      });
+    }
     
     // Create or update files AFTER package installation
     for (const file of filteredFiles) {
@@ -354,7 +421,7 @@ export async function POST(request: NextRequest) {
           
         } catch (writeError) {
           console.error(`[apply-ai-code] E2B file write error:`, writeError);
-          throw writeError;
+          throw writeError as Error;
         }
         
         
@@ -491,7 +558,7 @@ with open(file_path, 'w') as f:
 print(f"Auto-generated: {file_path}")
           `);
           results.filesCreated.push('src/index.css (with Tailwind)');
-        } catch (error) {
+        } catch {
           results.errors.push('Failed to create index.css with Tailwind');
         }
       }