chore: add .env.example template

Add .env.example with dummy values for all required environment
variables. Users can copy this to .env and fill in actual values.

.env.example

@@ -0,0 +1,86 @@
+# Dummy environment variables for MCP servers
+# Replace with actual values as needed
+
+# KiCAD
+KICAD_HOST=host.docker.internal
+KICAD_PORT=5555
+
+# Proxmox
+PROXMOX_HOST=https://proxmox.example.com:8006
+PROXMOX_USER=root@pam
+PROXMOX_TOKEN=dummy-token-replace-with-real-token
+PROXMOX_NODE=pve
+
+# Cloudron
+CLOUDRON_URL=https://cloudron.example.com
+CLOUDRON_TOKEN=dummy-cloudron-token-replace-with-real
+
+# Context7 (Upstash Redis)
+UPSTASH_REDIS_REST_URL=https://dummy-redis-url.upstash.io
+UPSTASH_REDIS_REST_TOKEN=dummy-redis-token-replace-with-real
+
+# Nextcloud
+NEXTCLOUD_HOST=https://nextcloud.example.com
+NEXTCLOUD_USERNAME=admin
+NEXTCLOUD_APP_PASSWORD=dummy-app-password-replace-with-real
+
+# Ghost (defaults already set in docker-compose)
+GHOST_API_URL=http://localhost:2368
+GHOST_ADMIN_API_KEY=012345678901234567890123:0123456789012345678901234567890123456789012345678901234567890123
+
+# DocSpace
+DOCSPACE_HOST=https://docspace.example.com
+DOCSPACE_TOKEN=dummy-docspace-token-replace-with-real
+
+# WordPress
+WORDPRESS_URL=https://wordpress.example.com
+WORDPRESS_USERNAME=admin
+WORDPRESS_APPLICATION_PASSWORD=dummy-app-password-replace-with-real
+
+# Discourse
+DISCOURSE_URL=https://discourse.example.com
+DISCOURSE_API_KEY=dummy-api-key-replace-with-real
+DISCOURSE_API_USERNAME=admin
+
+# IMAP
+IMAP_HOST=imap.example.com
+IMAP_PORT=993
+IMAP_USERNAME=user@example.com
+IMAP_PASSWORD=dummy-password-replace-with-real
+
+# Postiz
+POSTIZ_URL=https://postiz.example.com
+POSTIZ_API_KEY=dummy-api-key-replace-with-real
+
+# Matomo
+MATOMO_URL=https://matomo.example.com
+MATOMO_TOKEN=dummy-token-replace-with-real
+
+# Bitwarden
+BITWARDEN_CLIENT_ID=dummy-client-id
+BITWARDEN_CLIENT_SECRET=dummy-client-secret
+BITWARDEN_PASSWORD=dummy-password
+BITWARDEN_SERVER_URL=https://vault.bitwarden.com
+
+# Snipe-IT
+SNIPEIT_URL=https://snipeit.example.com
+SNIPEIT_TOKEN=dummy-token-replace-with-real
+
+# Redmine
+REDMINE_URL=https://redmine.example.com
+REDMINE_API_KEY=dummy-api-key-replace-with-real
+
+# Elasticsearch
+ELASTICSEARCH_URL=http://localhost:9200
+ELASTICSEARCH_USERNAME=elastic
+ELASTICSEARCH_PASSWORD=dummy-password-replace-with-real
+
+# Audiobook
+AUDIOBOOK_ROOT=/audiobooks
+
+# Draw.io (default in compose)
+DRAWIO_URL=https://app.diagrams.net
+
+# Penpot (default URL in compose)
+PENPOT_URL=https://design.penpot.app
+PENPOT_TOKEN=dummy-penpot-token-replace-with-real