feat: add Chinese 12x12 bitmap font (21075 glyphs) and fix boot gate

- Add ChineseFont12x12.h: U+4E00-U+9FFF CJK coverage, 535KB flash

- Add gen_chinese_font.mjs: @napi-rs/canvas based font generator tool

- Enable CJK rendering in MessageRenderer and CannedMessageModule

- Remove boot confirmation gate (required 2s button hold, caused shutdown loop)

- Update partition table: app 2.75MB, OTA 192KB, spiffs 1MB

- Update CHANGELOG

code/firmware-2.7.15.567b8ea/tools/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "tools",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "type": "commonjs",
+  "dependencies": {
+    "@napi-rs/canvas": "^0.1.97"
+  }
+}