Fix fan oscillate toggle handling and add EGLO fan codes

[dankarization]

Summary

• treat oscillate as a one-shot toggle command instead of replaying it on every later speed change
• restore the saved oscillating attribute from Home Assistant state
• add EGLO fan code files 1230 and 1231
• document the new EGLO device codes in the fan docs

Why

Issue #1112 describes fans where the oscillation command is a toggle that should only be sent once. The previous fan logic stored oscillating=True and then resent the raw oscillate command on every subsequent speed change, which flipped oscillation back off on affected devices.

Validation

• python3 -m json.tool for both new EGLO code files
• python3 -m compileall custom_components/smartir/fan.py
• isolated behavior check for the affected fan flow: turn_on -> oscillate(true) -> set_percentage -> set_percentage now sends speed, oscillate, speed, speed