docs: load media examples from disk instead of inline base64 (#3108)

docs_src/media/tutorial002.py

@@ -1,24 +1,21 @@
-import base64
+from pathlib import Path
 
 from mcp.server import MCPServer
 from mcp.server.mcpserver import Audio, Image
 
 mcp = MCPServer("Brand kit")
 
-LOGO_PNG = base64.b64decode(
-    "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAIAAACQd1PeAAAADElEQVR4nGOQ9bsBAAHPAURf8l/aAAAAAElFTkSuQmCC"
-)
-
-CHIME_WAV = base64.b64decode("UklGRjQAAABXQVZFZm10IBAAAAABAAEAQB8AAIA+AAACABAAZGF0YRAAAAAAAAAAAAAAAAAAAAAAAAAA")
+LOGO_FILE = Path(__file__).parent / "logo.png"
+CHIME_FILE = Path(__file__).parent / "chime.wav"
 
 
 @mcp.tool()
 def logo() -> Image:
     """The brand logo as a PNG."""
-    return Image(data=LOGO_PNG, format="png")
+    return Image(path=LOGO_FILE)
 
 
 @mcp.tool()
 def chime() -> Audio:
     """The notification chime as a WAV."""
-    return Audio(data=CHIME_WAV, format="wav")
+    return Audio(path=CHIME_FILE)