feat: add Vision LLM integration (CLIP + Qwen3-VL cascade)

- Add Qwen3-VL dynamic management (start/stop/status CLI)
- Add CLIP + Qwen3-VL cascade detection strategy
- Add Vision CLI commands (vision start/stop/status, detect)
- Add cascade_vision processor module
- Add clip processor module
- Add qwen_vl_manager module

Changes:
- scripts/start_qwen3vl.sh, stop_qwen3vl.sh: Qwen3-VL management scripts
- src/core/vision/: Qwen3-VL manager module
- src/core/processor/cascade_vision.rs: CLIP + Qwen3-VL cascade logic
- src/core/processor/clip.rs: CLIP classification and detection
- src/api/clip_api.rs: CLIP API endpoints
- src/cli/vision.rs: Vision CLI implementation
- src/cli/args.rs: Add Vision and Detect commands
- src/main.rs: Integrate Vision CLI
- src/core/mod.rs: Add vision module
- src/core/processor/mod.rs: Add cascade_vision module

scripts/stop_qwen3vl.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+# Stop Qwen3-VL server
+
+PID_FILE="/tmp/qwen3vl.pid"
+
+if [ -f "$PID_FILE" ]; then
+    PID=$(cat "$PID_FILE")
+    if ps -p "$PID" > /dev/null 2>&1; then
+        kill "$PID"
+        sleep 2
+        if ps -p "$PID" > /dev/null 2>&1; then
+            kill -9 "$PID"
+        fi
+        echo "Qwen3-VL stopped (PID: $PID)"
+    else
+        echo "Process already stopped (PID: $PID)"
+    fi
+    rm "$PID_FILE"
+else
+    echo "No PID file found at $PID_FILE"
+    echo "Searching for running process..."
+    RUNNING_PID=$(ps aux | grep "Qwen3VL-8B" | grep -v grep | awk '{print $2}')
+    if [ -n "$RUNNING_PID" ]; then
+        echo "Found running process (PID: $RUNNING_PID)"
+        kill "$RUNNING_PID"
+        echo "Process killed"
+    else
+        echo "No running process found"
+    fi
+fi