Feat: add admin CLI and admin service (#10186)

### What problem does this PR solve?

Introduce new feature: RAGFlow system admin service and CLI

### Introduction

Admin Service is a dedicated management component designed to monitor,
maintain, and administrate the RAGFlow system. It provides comprehensive
tools for ensuring system stability, performing operational tasks, and
managing users and permissions efficiently.

The service offers monitoring of critical components, including the
RAGFlow server, Task Executor processes, and dependent services such as
MySQL, Infinity / Elasticsearch, Redis, and MinIO. It automatically
checks their health status, resource usage, and uptime, and performs
restarts in case of failures to minimize downtime.

For user and system management, it supports listing, creating,
modifying, and deleting users and their associated resources like
knowledge bases and Agents.

Built with scalability and reliability in mind, the Admin Service
ensures smooth system operation and simplifies maintenance workflows.

It consists of a server-side Service and a command-line client (CLI),
both implemented in Python. User commands are parsed using the Lark
parsing toolkit.

- **Admin Service**: A backend service that interfaces with the RAGFlow
system to execute administrative operations and monitor its status.
- **Admin CLI**: A command-line interface that allows users to connect
to the Admin Service and issue commands for system management.

### Starting the Admin Service

1. Before start Admin Service, please make sure RAGFlow system is
already started.

2.  Run the service script:
    ```bash
    python admin/admin_server.py
    ```
The service will start and listen for incoming connections from the CLI
on the configured port.

### Using the Admin CLI

1.  Ensure the Admin Service is running.
2.  Launch the CLI client:
    ```bash
    python admin/admin_client.py -h 0.0.0.0 -p 9381
## Supported Commands
Commands are case-insensitive and must be terminated with a semicolon
(`;`).
### Service Management Commands
-  [x] `LIST SERVICES;`
    -   Lists all available services within the RAGFlow system.
-  [ ] `SHOW SERVICE <id>;`
- Shows detailed status information for the service identified by
`<id>`.
-  [ ] `STARTUP SERVICE <id>;`
    -   Attempts to start the service identified by `<id>`.
-  [ ] `SHUTDOWN SERVICE <id>;`
- Attempts to gracefully shut down the service identified by `<id>`.
-  [ ] `RESTART SERVICE <id>;`
    -   Attempts to restart the service identified by `<id>`.
### User Management Commands
-  [x] `LIST USERS;`
    -   Lists all users known to the system.
-  [ ] `SHOW USER '<username>';`
- Shows details and permissions for the specified user. The username
must be enclosed in single or double quotes.
-  [ ] `DROP USER '<username>';`
    -   Removes the specified user from the system. Use with caution.
-  [ ] `ALTER USER PASSWORD '<username>' '<new_password>';`
    -   Changes the password for the specified user.
### Data and Agent Commands
-  [ ] `LIST DATASETS OF '<username>';`
    -   Lists the datasets associated with the specified user.
-  [ ] `LIST AGENTS OF '<username>';`
    -   Lists the agents associated with the specified user.
### Meta-Commands
Meta-commands are prefixed with a backslash (`\`).
-   `\?` or `\help`
    -   Shows help information for the available commands.
-   `\q` or `\quit`
    -   Exits the CLI application.
## Examples
```commandline
admin> list users;
+-------------------------------+------------------------+-----------+-------------+
| create_date                   | email                  | is_active | nickname    |
+-------------------------------+------------------------+-----------+-------------+
| Fri, 22 Nov 2024 16:03:41 GMT | jeffery@infiniflow.org | 1         | Jeffery     |
| Fri, 22 Nov 2024 16:10:55 GMT | aya@infiniflow.org     | 1         | Waterdancer |
+-------------------------------+------------------------+-----------+-------------+
admin> list services;
+-------------------------------------------------------------------------------------------+-----------+----+---------------+-------+----------------+
| extra                                                                                     | host      | id | name          | port  | service_type   |
+-------------------------------------------------------------------------------------------+-----------+----+---------------+-------+----------------+
| {}                                                                                        | 0.0.0.0   | 0  | ragflow_0     | 9380  | ragflow_server |
| {'meta_type': 'mysql', 'password': 'infini_rag_flow', 'username': 'root'}                 | localhost | 1  | mysql         | 5455  | meta_data      |
| {'password': 'infini_rag_flow', 'store_type': 'minio', 'user': 'rag_flow'}                | localhost | 2  | minio         | 9000  | file_store     |
| {'password': 'infini_rag_flow', 'retrieval_type': 'elasticsearch', 'username': 'elastic'} | localhost | 3  | elasticsearch | 1200  | retrieval      |
| {'db_name': 'default_db', 'retrieval_type': 'infinity'}                                   | localhost | 4  | infinity      | 23817 | retrieval      |
| {'database': 1, 'mq_type': 'redis', 'password': 'infini_rag_flow'}                        | localhost | 5  | redis         | 6379  | message_queue  |
+-------------------------------------------------------------------------------------------+-----------+----+---------------+-------+----------------+
```

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

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

api/db/services/user_service.py

@@ -45,22 +45,22 @@ class UserService(CommonService):
     def query(cls, cols=None, reverse=None, order_by=None, **kwargs):
         if 'access_token' in kwargs:
             access_token = kwargs['access_token']
-            
+
             # Reject empty, None, or whitespace-only access tokens
             if not access_token or not str(access_token).strip():
                 logging.warning("UserService.query: Rejecting empty access_token query")
                 return cls.model.select().where(cls.model.id == "INVALID_EMPTY_TOKEN")  # Returns empty result
-            
+
             # Reject tokens that are too short (should be UUID, 32+ chars)
             if len(str(access_token).strip()) < 32:
                 logging.warning(f"UserService.query: Rejecting short access_token query: {len(str(access_token))} chars")
                 return cls.model.select().where(cls.model.id == "INVALID_SHORT_TOKEN")  # Returns empty result
-            
+
             # Reject tokens that start with "INVALID_" (from logout)
             if str(access_token).startswith("INVALID_"):
                 logging.warning("UserService.query: Rejecting invalidated access_token")
                 return cls.model.select().where(cls.model.id == "INVALID_LOGOUT_TOKEN")  # Returns empty result
-        
+
         # Call parent query method for valid requests
         return super().query(cols=cols, reverse=reverse, order_by=order_by, **kwargs)
 
@@ -140,6 +140,12 @@ class UserService(CommonService):
             cls.model.id == user_id,
             cls.model.is_superuser == 1).count() > 0
 
+    @classmethod
+    @DB.connection_context()
+    def get_all_users(cls):
+        users = cls.model.select()
+        return list(users)
+
 
 class TenantService(CommonService):
     """Service class for managing tenant-related database operations.