feat: add plugin dependency pipeline and HTML rendering service

- Implemented a new dependency pipeline for plugins to manage Python package dependencies, including conflict detection and automatic installation of missing dependencies.
- Introduced an HTML rendering service that utilizes existing browsers to render HTML content as PNG images, with support for various configurations and error handling.

src/plugin_runtime/capabilities/render.py

@@ -0,0 +1,121 @@
+"""插件运行时的浏览器渲染能力。"""
+
+from typing import Any, Dict
+
+from src.common.logger import get_logger
+from src.services.html_render_service import HtmlRenderRequest, get_html_render_service
+
+logger = get_logger("plugin_runtime.integration")
+
+
+class RuntimeRenderCapabilityMixin:
+    """插件运行时的浏览器渲染能力混入。"""
+
+    @staticmethod
+    def _coerce_int(value: Any, default: int) -> int:
+        """将任意值尽量转换为整数。
+
+        Args:
+            value: 原始输入值。
+            default: 转换失败时返回的默认值。
+
+        Returns:
+            int: 规范化后的整数结果。
+        """
+
+        try:
+            return int(value)
+        except (TypeError, ValueError):
+            return default
+
+    @staticmethod
+    def _coerce_float(value: Any, default: float) -> float:
+        """将任意值尽量转换为浮点数。
+
+        Args:
+            value: 原始输入值。
+            default: 转换失败时返回的默认值。
+
+        Returns:
+            float: 规范化后的浮点结果。
+        """
+
+        try:
+            return float(value)
+        except (TypeError, ValueError):
+            return default
+
+    @staticmethod
+    def _coerce_bool(value: Any, default: bool = False) -> bool:
+        """将任意值转换为布尔值。
+
+        Args:
+            value: 原始输入值。
+            default: 输入为空时返回的默认值。
+
+        Returns:
+            bool: 规范化后的布尔结果。
+        """
+
+        if value is None:
+            return default
+        if isinstance(value, str):
+            normalized_value = value.strip().lower()
+            if normalized_value in {"0", "false", "no", "off"}:
+                return False
+            if normalized_value in {"1", "true", "yes", "on"}:
+                return True
+        return bool(value)
+
+    def _build_html_render_request(self, args: Dict[str, Any]) -> HtmlRenderRequest:
+        """根据 capability 调用参数构造渲染请求。
+
+        Args:
+            args: capability 调用参数。
+
+        Returns:
+            HtmlRenderRequest: 结构化后的渲染请求。
+        """
+
+        viewport = args.get("viewport", {})
+        viewport_width = 900
+        viewport_height = 500
+        if isinstance(viewport, dict):
+            viewport_width = self._coerce_int(viewport.get("width"), viewport_width)
+            viewport_height = self._coerce_int(viewport.get("height"), viewport_height)
+
+        return HtmlRenderRequest(
+            html=str(args.get("html", "") or ""),
+            selector=str(args.get("selector", "body") or "body"),
+            viewport_width=viewport_width,
+            viewport_height=viewport_height,
+            device_scale_factor=self._coerce_float(args.get("device_scale_factor"), 2.0),
+            full_page=self._coerce_bool(args.get("full_page"), False),
+            omit_background=self._coerce_bool(args.get("omit_background"), False),
+            wait_until=str(args.get("wait_until", "load") or "load"),
+            wait_for_selector=str(args.get("wait_for_selector", "") or ""),
+            wait_for_timeout_ms=self._coerce_int(args.get("wait_for_timeout_ms"), 0),
+            timeout_ms=self._coerce_int(args.get("timeout_ms"), 0),
+            allow_network=self._coerce_bool(args.get("allow_network"), False),
+        )
+
+    async def _cap_render_html2png(self, plugin_id: str, capability: str, args: Dict[str, Any]) -> Any:
+        """将 HTML 内容渲染为 PNG 图片。
+
+        Args:
+            plugin_id: 调用该能力的插件 ID。
+            capability: 当前能力名称。
+            args: 能力调用参数。
+
+        Returns:
+            Any: 标准化后的能力返回结构。
+        """
+
+        del plugin_id, capability
+        try:
+            request = self._build_html_render_request(args)
+            result = await get_html_render_service().render_html_to_png(request)
+            return {"success": True, "result": result.to_payload()}
+        except Exception as exc:
+            logger.error(f"[cap.render.html2png] 执行失败: {exc}", exc_info=True)
+            return {"success": False, "error": str(exc)}