feat: GiteaHubSync v1.0.0 — fnOS 原生应用：Gitea→GitHub 镜像同步

- 每次推送到飞牛 Gitea（3000 端口）的代码 10 秒内自动镜像到 GitHub 7 个私有仓库
  （SMB_Android / DCU_APP / GD32E50X_BOOT / DCU_DesktopController / Motor_v2 /
  DCU_ECAT_Master / GD32_BOOT），真镜像语义（删分支/标签同步删）
- 标准 .fpk 原生应用：不进 Docker，依赖 python312，安装后进入应用中心已安装列表
  和桌面启动台，支持启动/停止/重启/卸载，NAS 重启自动恢复
- 控制面板（:8899）：自动同步开关、立即同步、仓库状态、同步日志、打开 Gitea
- GitHub 推送走 SSH 22 端口直连（HTTPS 443 本地网络被断），部署私钥随应用本地分发
- 附 fnos-install.js（命令行自动安装）、build.sh（重新构建 fpk）、genicon.py（图标生成）

注意：GitHub 部署私钥（GiteaHubSync/app/ssh/id_ed25519）与打包产物 .fpk
按 .gitignore 规则不进仓库，仅保留在工作目录本地分发。

genicon.py

@@ -0,0 +1,134 @@
+#!/usr/bin/env python3
+"""Generate GiteaHubSync app icons (pure stdlib, no PIL).
+Design: rounded gradient tile (blue -> teal) + white double sync arrows."""
+import os
+import struct
+import zlib
+
+BASE = os.path.join(os.path.dirname(os.path.abspath(__file__)), "GiteaHubSync")
+
+
+class Canvas:
+    def __init__(self, w, h, scale=4):
+        self.w, self.h, self.s = w, h, scale
+        self.W, self.H = w * scale, h * scale
+        self.px = [(0, 0, 0, 0)] * (self.W * self.H)
+
+    def _set(self, x, y, rgba):
+        if 0 <= x < self.W and 0 <= y < self.H:
+            i = y * self.W + x
+            r, g, b, a = rgba
+            orr, og, ob, oa = self.px[i]
+            na = a / 255.0 + oa / 255.0 * (1 - a / 255.0)
+            if na == 0:
+                self.px[i] = (0, 0, 0, 0)
+            else:
+                nr = (r * a / 255.0 + orr * oa / 255.0 * (1 - a / 255.0)) / na
+                ng = (g * a / 255.0 + og * ob / 255.0 * (1 - a / 255.0)) / na
+                nb = (b * a / 255.0 + ob * oa / 255.0 * (1 - a / 255.0)) / na
+                self.px[i] = (int(nr), int(ng), int(nb), int(na * 255))
+
+    def line(self, x1, y1, x2, y2, thick, rgba):
+        steps = int(max(abs(x2 - x1), abs(y2 - y1)) * 2) + 1
+        for i in range(steps + 1):
+            t = i / steps
+            cx, cy = x1 + (x2 - x1) * t, y1 + (y2 - y1) * t
+            r = thick / 2.0
+            for yy in range(int(cy - r) - 1, int(cy + r) + 2):
+                for xx in range(int(cx - r) - 1, int(cx + r) + 2):
+                    if (xx - cx) ** 2 + (yy - cy) ** 2 <= r * r:
+                        self._set(xx, yy, rgba)
+
+    def triangle(self, pts, rgba):
+        ys = [p[1] for p in pts]
+        for y in range(int(min(ys)), int(max(ys)) + 1):
+            xints = []
+            for i in range(3):
+                x1, y1 = pts[i]
+                x2, y2 = pts[(i + 1) % 3]
+                if y1 == y2:
+                    continue
+                if min(y1, y2) <= y < max(y1, y2):
+                    t = (y - y1) / (y2 - y1)
+                    xints.append(x1 + t * (x2 - x1))
+            if len(xints) >= 2:
+                xints.sort()
+                for x in range(int(xints[0]), int(xints[-1]) + 1):
+                    self._set(x, y, rgba)
+
+    def gradient_fill(self, x, y, w, h, rad, c1, c2):
+        for yy in range(y, y + h):
+            t = (yy - y) / max(h - 1, 1)
+            r = int(c1[0] + (c2[0] - c1[0]) * t)
+            g = int(c1[1] + (c2[1] - c1[1]) * t)
+            b = int(c1[2] + (c2[2] - c1[2]) * t)
+            for xx in range(x, x + w):
+                dx = max(x + rad - xx, xx - (x + w - 1 - rad), 0)
+                dy = max(y + rad - yy, yy - (y + h - 1 - rad), 0)
+                if dx * dx + dy * dy <= rad * rad:
+                    self._set(xx, yy, (r, g, b, 255))
+
+    def save(self, path):
+        s = self.s
+        rows = []
+        for y in range(self.h):
+            row = bytearray([0])
+            for x in range(self.w):
+                rs = gs = bs = as_ = 0
+                cnt = 0
+                for dy in range(s):
+                    for dx in range(s):
+                        p = self.px[(y * s + dy) * self.W + (x * s + dx)]
+                        rs += p[0]; gs += p[1]; bs += p[2]; as_ += p[3]
+                        cnt += 1
+                row += bytes((rs // cnt, gs // cnt, bs // cnt, as_ // cnt))
+            rows.append(bytes(row))
+        raw = b"".join(rows)
+
+        def chunk(tag, data):
+            c = struct.pack(">I", len(data)) + tag + data
+            return c + struct.pack(">I", zlib.crc32(tag + data) & 0xFFFFFFFF)
+
+        png = b"\x89PNG\r\n\x1a\n"
+        png += chunk(b"IHDR", struct.pack(">IIBBBBB", self.w, self.h, 8, 6, 0, 0, 0))
+        png += chunk(b"IDAT", zlib.compress(raw, 9))
+        png += chunk(b"IEND", b"")
+        with open(path, "wb") as f:
+            f.write(png)
+
+
+def draw_icon(size):
+    c = Canvas(size, size)
+    S = c.s
+    W = c.W
+    m = int(size * 0.05) * S
+    # 渐变圆角瓷砖：蓝 -> 青
+    c.gradient_fill(m, m, W - 2 * m, c.H - 2 * m, int(size * 0.22) * S,
+                    (37, 99, 235), (13, 148, 136))
+    white = (255, 255, 255, 255)
+    t = int(size * 0.055) * S          # 箭杆粗细
+    ah = int(size * 0.11) * S          # 箭头大小
+    y1 = int(size * 0.42) * S          # 上箭头中心线
+    y2 = int(size * 0.58) * S          # 下箭头中心线
+    # 上箭头：向左的杆 + 左箭头
+    c.line(W * 0.40, y1, W * 0.68, y1, t, white)
+    c.triangle([(W * 0.70, y1), (W * 0.70 - ah, y1 - ah * 0.62), (W * 0.70 - ah, y1 + ah * 0.62)], white)
+    # 下箭头：向右的杆 + 右箭头
+    c.line(W * 0.32, y2, W * 0.60, y2, t, white)
+    c.triangle([(W * 0.30, y2), (W * 0.30 + ah, y2 - ah * 0.62), (W * 0.30 + ah, y2 + ah * 0.62)], white)
+    return c
+
+
+def main():
+    for size, rel in [(256, "ICON_256.PNG"), (64, "ICON.PNG")]:
+        draw_icon(size).save(os.path.join(BASE, rel))
+        print("built", rel)
+    img = os.path.join(BASE, "app", "ui", "images")
+    os.makedirs(img, exist_ok=True)
+    for size, name in [(256, "icon_256.png"), (64, "icon_64.png")]:
+        draw_icon(size).save(os.path.join(img, name))
+        print("built", name)
+
+
+if __name__ == "__main__":
+    main()