refactor: consolidate blockchain explorer into single app and update backup ignore patterns

- Remove standalone explorer-web app (README, HTML, package files)
- Add /web endpoint to blockchain-explorer for web interface access
- Update .gitignore to exclude application backup archives (*.tar.gz, *.zip)
- Add backup documentation files to .gitignore (BACKUP_INDEX.md, README.md)
- Consolidate explorer functionality into main blockchain-explorer application

apps/wallet/src/app/main.py

@@ -0,0 +1,27 @@
+from __future__ import annotations
+
+from fastapi import FastAPI
+
+from .api_jsonrpc import router as jsonrpc_router
+from .api_rest import router as receipts_router
+from .settings import settings
+
+
+def create_app() -> FastAPI:
+    app = FastAPI(title=settings.app_name, debug=settings.debug)
+    app.include_router(receipts_router)
+    app.include_router(jsonrpc_router)
+    
+    # Add health check endpoint
+    @app.get("/health")
+    async def health_check():
+        return {
+            "status": "ok",
+            "env": "dev",
+            "python_version": "3.13.5"
+        }
+    
+    return app
+
+
+app = create_app()