⚡ Bolt: Fix code style and update PR description

Applies `black` formatting to `fastdeploy/router/router.py` to fix CI failure.
Updates the PR description to strictly follow the FastDeploy template, including correct header names and checklist items.

Co-authored-by: ZeyuChen <1371212+ZeyuChen@users.noreply.github.com>

Author: google-labs-jules[bot]

fastdeploy/router/router.py

@@ -243,9 +243,7 @@ async def _generate(
             raise RuntimeError("Router session not initialized")
 
         timeout = aiohttp.ClientTimeout(total=self.timeout)
-        tasks = [
-            self.session.post(f"{url}/{endpoint}", json=modified_request, timeout=timeout) for url in urls
-        ]
+        tasks = [self.session.post(f"{url}/{endpoint}", json=modified_request, timeout=timeout) for url in urls]
         results = await asyncio.gather(*tasks, return_exceptions=True)
 
         num_results = len(results)
@@ -278,9 +276,7 @@ async def stream_results():
                 raise RuntimeError("Router session not initialized")
 
             timeout = aiohttp.ClientTimeout(total=self.timeout)
-            tasks = [
-                self.session.post(f"{url}/{endpoint}", json=modified_request, timeout=timeout) for url in urls
-            ]
+            tasks = [self.session.post(f"{url}/{endpoint}", json=modified_request, timeout=timeout) for url in urls]
             results = await asyncio.gather(*tasks, return_exceptions=True)
 
             # Release unused responses
@@ -443,6 +439,7 @@ async def monitor_instance_health(self, interval_secs: float = 5.0):
         """
         Continuously check the health of prefill, decode, and mixed instances and remove unhealthy ones.
         """
+
         async def check(inst):
             try:
                 if self.session is None: