[BugFix][Metrics] Fix Prometheus Multiprocess Metrics Issues and Add ZMQ Communication Metrics (#5185)

* [Feature] add metrics for ZMQ and fix multiprocess metrics

* fix test_metrics.py

---------

Co-authored-by: Jiaxin Sui <95567040+plusNew001@users.noreply.github.com>

fastdeploy/__init__.py

@@ -33,6 +33,15 @@ if os.getenv("PROMETHEUS_MULTIPROC_DIR", "") == "":
 
 import typing
 
+# first import prometheus setup to set PROMETHEUS_MULTIPROC_DIR
+# otherwise, the Prometheus package will be imported first,
+# which will prevent correct multi-process setup
+from fastdeploy.metrics.prometheus_multiprocess_setup import (
+    setup_multiprocess_prometheus,
+)
+
+setup_multiprocess_prometheus()
+
 from paddleformers.utils.log import logger as pf_logger
 
 from fastdeploy.engine.sampling_params import SamplingParams