Refactor project structure to organize APIs (#24)

* Refactor project structure "api"
* fix bug conversione delle valute fiat in stablecoin in BinanceWrapper
* Refactor: WrapperHandler for managing API wrappers with retry logic; update related modules and tests
* Refactor: Update ProductInfo and Price classes to include aggregation methods; remove standalone aggregation functions
* fix docs

src/app/api/news/cryptopanic_api.py

@@ -0,0 +1,79 @@
+import os
+from typing import Any
+import requests
+from enum import Enum
+from app.api.base.news import NewsWrapper, Article
+
+
+class CryptoPanicFilter(Enum):
+    RISING = "rising"
+    HOT = "hot"
+    BULLISH = "bullish"
+    BEARISH = "bearish"
+    IMPORTANT = "important"
+    SAVED = "saved"
+    LOL = "lol"
+    ANY = ""
+
+class CryptoPanicKind(Enum):
+    NEWS = "news"
+    MEDIA = "media"
+    ALL = "all"
+
+def extract_articles(response: dict[str, Any]) -> list[Article]:
+    articles: list[Article] = []
+    if 'results' in response:
+        for item in response['results']:
+            article = Article()
+            article.source = item.get('source', {}).get('title', '')
+            article.time = item.get('published_at', '')
+            article.title = item.get('title', '')
+            article.description = item.get('description', '')
+            articles.append(article)
+    return articles
+
+class CryptoPanicWrapper(NewsWrapper):
+    """
+    A wrapper for the CryptoPanic API (Documentation: https://cryptopanic.com/developers/api/)
+    Requires an API key set in the environment variable CRYPTOPANIC_API_KEY.
+    It is free to use, but has rate limits and restrictions based on the plan type (the free plan is 'developer' with 100 req/month).
+    Supports different plan types via the CRYPTOPANIC_API_PLAN environment variable (developer, growth, enterprise).
+    """
+
+    def __init__(self):
+        self.api_key = os.getenv("CRYPTOPANIC_API_KEY", "")
+        assert self.api_key, "CRYPTOPANIC_API_KEY environment variable not set"
+
+        # Set here for the future, but currently not needed
+        plan_type = os.getenv("CRYPTOPANIC_API_PLAN", "developer").lower()
+        assert plan_type in ["developer", "growth", "enterprise"], "Invalid CRYPTOPANIC_API_PLAN value"
+
+        self.base_url = f"https://cryptopanic.com/api/{plan_type}/v2"
+        self.filter = CryptoPanicFilter.ANY
+        self.kind = CryptoPanicKind.NEWS
+
+    def get_base_params(self) -> dict[str, str]:
+        params: dict[str, str] = {}
+        params['public'] = 'true' # recommended for app and bots
+        params['auth_token'] = self.api_key
+        params['kind'] = self.kind.value
+        if self.filter != CryptoPanicFilter.ANY:
+            params['filter'] = self.filter.value
+        return params
+
+    def set_filter(self, filter: CryptoPanicFilter):
+        self.filter = filter
+
+    def get_top_headlines(self, limit: int = 100) -> list[Article]:
+        return self.get_latest_news("", limit) # same endpoint so just call the other method
+
+    def get_latest_news(self, query: str, limit: int = 100) -> list[Article]:
+        params = self.get_base_params()
+        params['currencies'] = query
+
+        response = requests.get(f"{self.base_url}/posts/", params=params)
+        assert response.status_code == 200, f"Error fetching data: {response}"
+
+        json_response = response.json()
+        articles = extract_articles(json_response)
+        return articles[:limit]