Move api.settings to common.settings (#11036)

### What problem does this PR solve?

As title

### Type of change

- [x] Refactoring

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

rag/settings.py

@@ -13,40 +13,3 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 #
-import os
-import logging
-from common.file_utils import get_project_base_directory
-from common.misc_utils import pip_install_torch
-
-# Server
-RAG_CONF_PATH = os.path.join(get_project_base_directory(), "conf")
-
-DOC_MAXIMUM_SIZE = int(os.environ.get("MAX_CONTENT_LENGTH", 128 * 1024 * 1024))
-DOC_BULK_SIZE = int(os.environ.get("DOC_BULK_SIZE", 4))
-EMBEDDING_BATCH_SIZE = int(os.environ.get("EMBEDDING_BATCH_SIZE", 16))
-SVR_QUEUE_NAME = "rag_flow_svr_queue"
-SVR_CONSUMER_GROUP_NAME = "rag_flow_svr_task_broker"
-PAGERANK_FLD = "pagerank_fea"
-TAG_FLD = "tag_feas"
-
-PARALLEL_DEVICES = 0
-try:
-    pip_install_torch()
-    import torch.cuda
-    PARALLEL_DEVICES = torch.cuda.device_count()
-    logging.info(f"found {PARALLEL_DEVICES} gpus")
-except Exception:
-    logging.info("can't import package 'torch'")
-
-def print_rag_settings():
-    logging.info(f"MAX_CONTENT_LENGTH: {DOC_MAXIMUM_SIZE}")
-    logging.info(f"MAX_FILE_COUNT_PER_USER: {int(os.environ.get('MAX_FILE_NUM_PER_USER', 0))}")
-
-
-def get_svr_queue_name(priority: int) -> str:
-    if priority == 0:
-        return SVR_QUEUE_NAME
-    return f"{SVR_QUEUE_NAME}_{priority}"
-
-def get_svr_queue_names():
-    return [get_svr_queue_name(priority) for priority in [1, 0]]