Update ESPHome config to post-2022 syntax

[funzoneq]

Summary

• Imports of Software/open-air-mini.yaml fail in ESPHome Builder: platform: and board: under esphome: were deprecated in ESPHome 2022.1 and later removed. Chip selection now lives in a top-level esp32: block.
• ota: became a list of platforms in ESPHome 2024.6, so it would have failed on the next compile even after the first fix. Converted to the - platform: esphome list form.
• The arduino framework is pinned explicitly: recent ESPHome defaults to ESP-IDF, which is not what this config's fan: speed / pulse_counter setup has been tested against.

No behavioural change intended — this is a syntax migration only.

Config diff

diff --git a/Open AIR Mini/Software/open-air-mini.yaml b/Open AIR Mini/Software/open-air-mini.yaml
index c26b3ab..971781d 100644
--- a/Open AIR Mini/Software/open-air-mini.yaml	
+++ b/Open AIR Mini/Software/open-air-mini.yaml	
@@ -1,7 +1,10 @@
 esphome:
   name: open-air-mini
-  platform: ESP32
+
+esp32:
   board: esp32dev
+  framework:
+    type: arduino
 
 # Enable logging
 logger:
@@ -15,7 +18,8 @@ web_server:
 api:
 
 ota:
-  password: "9f2ab9aa715f573e2476e75a5ec7f4e7"
+  - platform: esphome
+    password: "9f2ab9aa715f573e2476e75a5ec7f4e7"
 
 wifi:
   ssid: !secret wifi_ssid

Test plan

• Software/open-air-mini.yaml passes Validate in ESPHome Builder
• Firmware compiles for esp32dev on the arduino framework
• Flashed unit boots, joins WiFi, and is adopted by Home Assistant
• Fan responds to speed changes and AIR Mini RPM reports plausible values
• OTA update succeeds against the new ota: block
• Disconnected mode still engages when the API drops (30s interval check)

Notes

• Not validated with esphome config locally — ESPHome is not installed on the authoring machine, so only YAML structure was checked. Builder's Validate is the real gate.
• Software/README.md still documents the pre-2022 layout in places; left untouched here to keep this diff to the syntax fix.

🤖 Generated with Claude Code

https://claude.ai/code/session_01P3ad48iZdxUzPwHPUYNJ4x