feat(pricing): optimise coingecko requests + add multi-level cache

[onyb]

This PR introduces a significant optimization to our CoinGecko API usage by implementing the following:

• a multi-level caching system (memcache + redis) to prevent unnecessary reads to Redis on every price request
• resolving chain id + contract addresses to coingecko id, to avoid making duplicate price lookups to the same underlying token

Request: (3 unique tokens)

curl -X 'POST' \
  'http://127.0.0.1:8000/api/pricing/v1/getPrices?vs_currency=usd' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '[
  {
    "address": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
    "chain_id": "0x1",
    "coin_type": "ETH"
  },
  {
    "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "chain_id": "0x2105",
    "coin_type": "ETH"
  },
  {
    "address": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "chain_id": "0x65",
    "coin_type": "SOL"
  }
]'

Response: (only 1 underlying price lookup)

[
  {
    "coin_type": "ETH",
    "chain_id": "0x1",
    "address": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
    "price": 0.999797,
    "vs_currency": "usd",
    "cache_status": "HIT"
  },
  {
    "coin_type": "SOL",
    "chain_id": "0x65",
    "address": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "price": 0.999797,
    "vs_currency": "usd",
    "cache_status": "HIT"
  },
  {
    "coin_type": "ETH",
    "chain_id": "0x2105",
    "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "price": 0.999797,
    "vs_currency": "usd",
    "cache_status": "MISS"
  }
]

[Douglashdaniel]

++