Implement context files feature - verified

- Added Context view with file list sidebar and text/image editor
- Added Context navigation item to sidebar
- Added deleteFile API method to Electron IPC
- Updated coding_prompt.md to include Step 1.5 for loading context files
- Updated mock Electron API to properly handle context directory
- Added test utilities for context view navigation

Features:
- Left panel with list of all context files
- Text editor for editing .md, .txt, and other text files
- Image preview for .png, .jpg, .gif, and other image files
- Add new text or image files via dialog
- Delete files with confirmation dialog
- Drag and drop file upload support
- Auto-save detection with Save button

All Playwright tests passing (9/9)
Deleted test file after verification

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

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

.automaker/coding_prompt.md

@@ -23,16 +23,46 @@ cat .automaker/feature_list.json | head -50
 # 5. Read progress notes from previous sessions
 cat claude-progress.txt
 
-# 6. Check recent git history
+# 6. Read the memory file - lessons learned from previous agents
+cat .automaker/memory.md
+
+# 7. Check recent git history
 git log --oneline -20
 
-# 7. Count remaining features
+# 8. Count remaining features
 cat .automaker/feature_list.json | grep -E '"status": "(backlog|in_progress)"' | wc -l
 ```
 
 Understanding the `app_spec.txt` is critical - it contains the full requirements
 for the application you're building.
 
+**IMPORTANT:** The `.automaker/memory.md` file contains critical lessons learned from previous sessions. Read it carefully to avoid repeating mistakes, especially around testing and mock setup.
+
+### STEP 1.5: LOAD PROJECT CONTEXT (MANDATORY)
+
+The `.automaker/context/` directory contains additional context files that provide important information for development. Always load these files to understand:
+- Design guidelines and requirements
+- API documentation
+- Reference implementations
+- Screenshots and mockups
+- Any other relevant context
+
+```bash
+# List all context files
+ls -la .automaker/context/
+
+# Read each context file (text files)
+for file in .automaker/context/*.md .automaker/context/*.txt; do
+  if [ -f "$file" ]; then
+    echo "=== $file ==="
+    cat "$file"
+    echo ""
+  fi
+done
+```
+
+**Note:** Image files (.png, .jpg, etc.) in the context directory should be referenced when they are relevant to the current feature. Use them as visual references for UI implementation.
+
 ### STEP 2: START SERVERS (IF NOT RUNNING)
 
 If `init.sh` exists, run it: