fix: configure gitea webhook auto-deploy, fix NVS CRC, and improve flash UI

- Add deploy-host.sh for webhook-triggered docker redeploy
- Update docker-compose.yml and nginx.conf for auto-pull setup
- Fix vite.config.js and admin router for deployment environment
- Fix NVS CRC seed to use 0xFFFFFFFF to match esp_rom_crc32_le
- Add dual-panel flash UI: esptool log + live 115200 serial monitor
- Auto-reset device via RTS after flash (no manual power cycle needed)
- Clean up Header.jsx debug title text

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

deploy-host.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+set -e
+
+PROJECT=/home/bellsystems/bellsystems-cp
+
+echo "Deploy started at $(date)"
+cd "$PROJECT"
+git fetch origin main
+git reset --hard origin/main
+docker compose up -d --build 2>&1
+echo "Deploy finished at $(date)"