Feat/ble hot cold treasure game

[MatteoCnda1]

PR: Add BLE Hot/Cold Treasure Hunt game using aioble & steami_screen

CLOSE : 411

DESCRIPTION:
A multi-device "Hot or Cold" game. One STeaMi acts as a 'Treasure' (beacon)
while the other acts as a 'Seeker' (scanner) to find it using RSSI signal
strength.

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CHANGES

• ADDED: BLE/BLE_HOT_COLD/main.py
  (Single-file app for both TREASURE and SEEKER roles)

• GAME MECHANICS:

  • Mode Selection: Interactive D-PAD menu (UP/DOWN/RIGHT) to pick role.
  • Signal Smoothing: Uses EMA (Exponential Moving Average) for stability.
  • Hysteresis: 8% dead-band to prevent UI/Sound flickering between zones.

• FEEDBACK SYSTEM:

  • Visual: Dynamic OLED faces (sad, sleeping, happy, love) + proximity gauge.
  • Audio: Variable buzzer patterns (frequency and rhythm) based on distance.

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PROXIMITY ZONES (0-100%):

[ Zone ] [ Range ] [ Face ] [ Audio Feedback ]
COLD 0 - 25% sad 1 low beep every 3s
WARM 25 - 50% sleeping 1 mid beep every 1.2s
HOT 50 - 75% happy 2 fast beeps every 500ms
BURNING 75 - 100% love 3 rapid bursts every 150ms

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CHECKLIST

[X] Tested on hardware (2x STeaMi boards)
[X] Zone transitions smooth (no flickering)
[X] Exit to menu functional (LEFT button)
[X] Buzzer patterns sync with visual feedback