refactor: 推送改为局域网直连设备，推送前清空画廊旧图

原走 Zectrix 公网 API + 设备 MAC，现改为直连局域网墨水屏设备（喵喵固件）
的 HTTP 接口：POST /upload 推送 PNG 触发刷屏。设备画廊按追加保存，故推送
前先 GET /images 清空旧图，避免图片越推越多、且避免 slideshow 模式轮播
到过期图。

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pusher.py

@@ -1,11 +1,12 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 """
-推送层 —— 调用 Zectrix 极趣云平台 API（仅用标准库 urllib，无第三方依赖）。
-文档：显示推送 / 设备管理。
+推送层 —— 直连局域网墨水屏设备（喵喵固件，仅用标准库 urllib，无第三方依赖）。
+固件开源：https://gitee.com/gxp666111/miaomiao（web/ 为设备自带管理页，可在浏览器打开
+http://<EPD_HOST>/ 调试同一套接口）。
 """
 import json
-import uuid
+import urllib.parse
 import urllib.request
 import urllib.error
 
@@ -13,53 +14,33 @@ import config
 
 
 def _request(method, path, headers=None, body=None):
-    url = f"{config.API_BASE}{path}"
-    h = {"X-API-Key": config.API_KEY}
-    if headers:
-        h.update(headers)
-    req = urllib.request.Request(url, data=body, headers=h, method=method)
+    url = f"http://{config.EPD_HOST}{path}"
+    req = urllib.request.Request(url, data=body, headers=headers or {}, method=method)
     try:
         with urllib.request.urlopen(req, timeout=30) as resp:
-            return json.loads(resp.read().decode("utf-8"))
+            return resp.read().decode("utf-8", "ignore")
     except urllib.error.HTTPError as e:
         raise RuntimeError(f"HTTP {e.code}: {e.read().decode('utf-8', 'ignore')}") from e
 
 
-def resolve_device_id():
-    """返回目标设备 ID：直接取 config.DEVICE_ID（硬件 MAC），未配置则报错。"""
-    if not config.DEVICE_ID:
-        raise RuntimeError("未配置设备 ID：请在 .env 设置 ZECTRIX_DEVICE_ID=<硬件 MAC>")
-    return config.DEVICE_ID
+def _list_gallery_names():
+    text = _request("GET", "/images")
+    return [item["name"] for item in json.loads(text).get("items", [])]
 
 
-def _multipart(fields, files):
-    """构造 multipart/form-data 请求体。fields: dict[str,str]; files: list[(name, filename, bytes, mime)]"""
-    boundary = uuid.uuid4().hex
-    crlf = b"\r\n"
-    buf = bytearray()
-    for k, v in fields.items():
-        buf += b"--" + boundary.encode() + crlf
-        buf += f'Content-Disposition: form-data; name="{k}"'.encode() + crlf + crlf
-        buf += str(v).encode() + crlf
-    for name, filename, content, mime in files:
-        buf += b"--" + boundary.encode() + crlf
-        buf += f'Content-Disposition: form-data; name="{name}"; filename="{filename}"'.encode() + crlf
-        buf += f"Content-Type: {mime}".encode() + crlf + crlf
-        buf += content + crlf
-    buf += b"--" + boundary.encode() + b"--" + crlf
-    return bytes(buf), f"multipart/form-data; boundary={boundary}"
+def _clear_gallery():
+    """设备画廊按追加保存，用完即删，使其始终只留最新一张。单张删除失败不影响后续上传。"""
+    for name in _list_gallery_names():
+        try:
+            _request("POST", f"/delete_image?name={urllib.parse.quote(name)}")
+        except Exception as e:
+            print(f"[推送] 清理画廊旧图 {name} 失败：{e}")
 
 
-def push_image(image_path, device_id=None, page_id=config.PAGE_ID, dither=config.DITHER):
-    """推送图片到设备显示。"""
-    device_id = device_id or resolve_device_id()
+def push_image(image_path):
+    """推送图片到局域网墨水屏设备：先清空画廊旧图，再上传新图触发显示刷新。"""
+    _clear_gallery()
     with open(image_path, "rb") as fp:
         content = fp.read()
-    fields = {"dither": "true" if dither else "false", "pageId": str(page_id)}
-    files = [("images", "dashboard.png", content, "image/png")]
-    body, content_type = _multipart(fields, files)
-    data = _request("POST", f"/devices/{device_id}/display/image",
-                    headers={"Content-Type": content_type}, body=body)
-    if data.get("code") != 0:
-        raise RuntimeError(f"推送失败: {data}")
-    return device_id, data
+    resp = _request("POST", "/upload", headers={"Content-Type": "image/png"}, body=content)
+    return config.EPD_HOST, resp