feat: 导入 NMEA-0183 GPS 协议解析库（node-nmea）

NMEA-0183 语句解析器，含 21 个语句类型 codec 与配套单元测试。

- codecs/：APB/BWC/DBT/GGA/GLL/GRMT/GSA/GSV/HDG/HDM/HDT/MWV/RDID/
  RMB/RMC/ROT/RSA/TXT/VTG/VWR/ZDA
- test/：各 codec 对应的 mocha 用例
- .github/workflows/：node与 npm-publish 流水线

许可证：MIT（原作者 James Penn）

codecs/GLL.js

@@ -0,0 +1,52 @@
+var helpers = require("../helpers.js")
+
+/*
+=== GLL - Geographic Position - Latitude/Longitude ===
+
+------------------------------------------------------------------------------
+        1       2 3        4 5         6 7   8
+        |       | |        | |         | |   |
+ $--GLL,llll.ll,a,yyyyy.yy,a,hhmmss.ss,a,m,*hh<CR><LF>
+------------------------------------------------------------------------------
+
+Field Number: 
+
+1. Latitude
+2. N or S (North or South)
+3. Longitude
+4. E or W (East or West)
+5. Universal Time Coordinated (UTC)
+6. Status A - Data Valid, V - Data Invalid
+7. FAA mode indicator (NMEA 2.3 and later)
+8. Checksum
+ */
+
+exports.TYPE = 'geo-position';
+exports.ID = 'GLL';
+
+exports.decode = function(fields) {
+        return {
+            sentence: exports.ID,
+            type: 'geo-position',
+            timestamp: fields[5],
+            lat: fields[1],
+            latPole: fields[2],
+            lon: fields[3],
+            lonPole: fields[4],
+            timestamp: fields[5],
+            status: fields[6] == 'A' ? 'valid' : 'invalid'
+        };
+    }
+
+exports.encode = function (talker, msg) {
+  var result = ['$' + talker + exports.ID];
+  result.push(helpers.encodeDegrees(msg.lat));
+  result.push(msg.latPole);
+  result.push(helpers.encodeDegrees(msg.lon));
+  result.push(msg.lonPole);
+  result.push(helpers.encodeTime(msg.timestamp));
+  result.push('A');
+  result.push('D');
+  var resultMsg = result.join(',');
+  return resultMsg + helpers.computeChecksum(resultMsg);
+}