Add openspool mini

[spuder]

Brief description of the changes

Add OpenSpool Mini Device

Type of changes

• New device
• Update existing device
• Removing a device
• General cleanup
• Other

Checklist:

• There are no passwords or secrets references in any examples.
  The only exceptions are !secret wifi_ssid and !secret wifi_password.
• The wifi or ethernet block has no static / manual ip address specified.
• The first configuration provided should be hardware definitions only.
  A more involved example can be provided in a separate configuration block.

[netlify]

✅ Deploy Preview for esphome-devices ready!

Name	Link
🔨 Latest commit	4fda1cb
🔍 Latest deploy log	https://app.netlify.com/sites/esphome-devices/deploys/673fd628d57dbf0008b1bf90
😎 Deploy Preview	https://deploy-preview-930--esphome-devices.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.
Lighthouse	1 paths audited Performance: 97 (🟢 up 5 from production) Accessibility: 86 (no change from production) Best Practices: 100 (no change from production) SEO: 89 (🔴 down 1 from production) PWA: 70 (no change from production) View the detailed breakdown and full score reports

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