refactor(core): replace float('inf') with math.inf

Replace float('inf') and float('-inf') with math.inf and -math.inf from the math module for better readability and performance. Also clean up imports and remove unused speed comparison code.

No breaking changes.

crawl4ai/deep_crawling/bfs_strategy.py

@@ -10,6 +10,7 @@ from .filters import FilterChain
 from .scorers import URLScorer
 from . import DeepCrawlStrategy  
 from ..types import AsyncWebCrawler, CrawlerRunConfig, CrawlResult
+from math import inf as infinity
 
 class BFSDeepCrawlStrategy(DeepCrawlStrategy):
     """
@@ -26,8 +27,8 @@ class BFSDeepCrawlStrategy(DeepCrawlStrategy):
         filter_chain: FilterChain = FilterChain(),
         url_scorer: Optional[URLScorer] = None,        
         include_external: bool = False,
-        score_threshold: float = float('-inf'),
-        max_pages: int = float('inf'),
+        score_threshold: float = -infinity,
+        max_pages: int = infinity,
         logger: Optional[logging.Logger] = None,
     ):
         self.max_depth = max_depth