refactor: extract ObserverService from DebugService for cleaner status access API

docs/design/server_client/prompt.md

@@ -35,7 +35,7 @@ openviking/service/
 - `SearchService`: find, search
 - `SessionService`: session, sessions, add_message, compress, extract
 - `RelationService`: link, unlink, relations
-- `DebugService`: get_queue_status, get_vikingdb_status, get_vlm_status, get_system_status, is_healthy
+- `DebugService`: observer (ObserverService)
 - `PackService`: export_ovpack, import_ovpack
 
 3. **创建 OpenVikingService 主类**：

docs/en/api/01-client.md

@@ -252,78 +252,21 @@ ov.OpenViking.reset()
 
 ---
 
-### get_status()
+## Debug Methods
 
-Get system status including health status of all components.
+For system health monitoring and component status, see [Debug API](./07-debug.md).
 
-**Signature**
-
-```python
-def get_status(self) -> SystemStatus
-```
-
-**Parameters**
-
-None.
-
-**Returns**
-
-| Type | Description |
-|------|-------------|
-| SystemStatus | System status object |
-
-**Return Structure**
-
-```python
-SystemStatus(
-    is_healthy=True,                    # Overall system health
-    components={                        # Component statuses
-        "queue": ComponentStatus(...),
-        "vikingdb": ComponentStatus(...),
-        "vlm": ComponentStatus(...)
-    },
-    errors=[]                           # Error list
-)
-```
-
-**Example**
-
-```python
-status = client.get_status()
-print(f"System healthy: {status.is_healthy}")
-print(f"Queue status: {status.components['queue'].is_healthy}")
-```
-
----
-
-### is_healthy()
-
-Quick health check.
-
-**Signature**
-
-```python
-def is_healthy(self) -> bool
-```
-
-**Parameters**
-
-None.
-
-**Returns**
-
-| Type | Description |
-|------|-------------|
-| bool | True if all components are healthy, False otherwise |
-
-**Example**
+**Quick Reference**
 
 ```python
+# Quick health check
 if client.is_healthy():
     print("System OK")
-else:
-    status = client.get_status()
-    print(f"Errors: {status.errors}")
+
+# Access component status via observer
+print(client.observer.vikingdb)
+print(client.observer.queue)
+print(client.observer.system)
 ```
 
 ---

docs/en/api/07-debug.md

@@ -0,0 +1,254 @@
+# Debug
+
+OpenViking provides debug and observability APIs for monitoring system health and component status.
+
+## API Reference
+
+### observer
+
+Property that provides convenient access to component status through `ObserverService`.
+
+**Signature**
+
+```python
+@property
+def observer(self) -> ObserverService
+```
+
+**Returns**
+
+| Type | Description |
+|------|-------------|
+| ObserverService | Service for accessing component status |
+
+**Example**
+
+```python
+import openviking as ov
+
+client = ov.OpenViking(path="./data")
+client.initialize()
+
+# Print component status directly
+print(client.observer.vikingdb)
+# Output:
+# [vikingdb] (healthy)
+# Collection  Index Count  Vector Count  Status
+# context     1            55            OK
+# TOTAL       1            55
+
+client.close()
+```
+
+---
+
+## ObserverService
+
+`ObserverService` provides properties for accessing individual component status.
+
+### queue
+
+Get queue system status.
+
+**Signature**
+
+```python
+@property
+def queue(self) -> ComponentStatus
+```
+
+**Returns**
+
+| Type | Description |
+|------|-------------|
+| ComponentStatus | Queue system status |
+
+**Example**
+
+```python
+print(client.observer.queue)
+# Output:
+# [queue] (healthy)
+# Queue                 Pending  In Progress  Processed  Errors  Total
+# Embedding             0        0            10         0       10
+# Semantic              0        0            10         0       10
+# TOTAL                 0        0            20         0       20
+```
+
+---
+
+### vikingdb
+
+Get VikingDB status.
+
+**Signature**
+
+```python
+@property
+def vikingdb(self) -> ComponentStatus
+```
+
+**Returns**
+
+| Type | Description |
+|------|-------------|
+| ComponentStatus | VikingDB status |
+
+**Example**
+
+```python
+print(client.observer.vikingdb)
+# Output:
+# [vikingdb] (healthy)
+# Collection  Index Count  Vector Count  Status
+# context     1            55            OK
+# TOTAL       1            55
+
+# Access specific properties
+print(client.observer.vikingdb.is_healthy)  # True
+print(client.observer.vikingdb.status)      # Status table string
+```
+
+---
+
+### vlm
+
+Get VLM (Vision Language Model) token usage status.
+
+**Signature**
+
+```python
+@property
+def vlm(self) -> ComponentStatus
+```
+
+**Returns**
+
+| Type | Description |
+|------|-------------|
+| ComponentStatus | VLM token usage status |
+
+**Example**
+
+```python
+print(client.observer.vlm)
+# Output:
+# [vlm] (healthy)
+# Model                          Provider      Prompt  Completion  Total  Last Updated
+# doubao-1-5-vision-pro-32k      volcengine    1000    500         1500   2024-01-01 12:00:00
+# TOTAL                                        1000    500         1500
+```
+
+---
+
+### system
+
+Get overall system status including all components.
+
+**Signature**
+
+```python
+@property
+def system(self) -> SystemStatus
+```
+
+**Returns**
+
+| Type | Description |
+|------|-------------|
+| SystemStatus | Overall system status |
+
+**Example**
+
+```python
+print(client.observer.system)
+# Output:
+# [queue] (healthy)
+# ...
+#
+# [vikingdb] (healthy)
+# ...
+#
+# [vlm] (healthy)
+# ...
+#
+# [system] (healthy)
+```
+
+---
+
+### is_healthy()
+
+Quick health check for the entire system.
+
+**Signature**
+
+```python
+def is_healthy(self) -> bool
+```
+
+**Returns**
+
+| Type | Description |
+|------|-------------|
+| bool | True if all components are healthy |
+
+**Example**
+
+```python
+if client.observer.is_healthy():
+    print("System OK")
+else:
+    print(client.observer.system)
+```
+
+---
+
+## Data Structures
+
+### ComponentStatus
+
+Status information for a single component.
+
+| Field | Type | Description |
+|-------|------|-------------|
+| name | str | Component name |
+| is_healthy | bool | Whether the component is healthy |
+| has_errors | bool | Whether the component has errors |
+| status | str | Status table string |
+
+**String Representation**
+
+```python
+print(component_status)
+# Output:
+# [component_name] (healthy)
+# Status table content...
+```
+
+---
+
+### SystemStatus
+
+Overall system status including all components.
+
+| Field | Type | Description |
+|-------|------|-------------|
+| is_healthy | bool | Whether the entire system is healthy |
+| components | Dict[str, ComponentStatus] | Status of each component |
+| errors | List[str] | List of error messages |
+
+**String Representation**
+
+```python
+print(system_status)
+# Output:
+# [queue] (healthy)
+# ...
+#
+# [vikingdb] (healthy)
+# ...
+#
+# [system] (healthy)
+# Errors: error1, error2  (if any)
+```

docs/en/concepts/01-architecture.md

@@ -73,7 +73,7 @@ The Service layer decouples business logic from the transport layer, enabling re
 | **ResourceService** | Resource import | add_resource, add_skill, wait_processed |
 | **RelationService** | Relation management | relations, link, unlink |
 | **PackService** | Import/export | export_ovpack, import_ovpack |
-| **DebugService** | Debug service | get_system_status, get_queue_status, get_vikingdb_status, get_vlm_status, is_healthy |
+| **DebugService** | Debug service | observer (ObserverService) |
 
 ## Dual-Layer Storage