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/RMC.js

@@ -0,0 +1,46 @@
+/*
+   === RMC - Recommended Minimum Navigation Information ===
+   
+   This is one of the sentences commonly emitted by GPS units.
+
+   ------------------------------------------------------------------------------
+              1      2    3    4    5     6  7   8   9   10 11 12
+              |      |    |    |    |     |  |   |   |    |  | |
+    $--RMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,a,x.x,x.x,xxxx,x.x,a*hh
+   ------------------------------------------------------------------------------
+
+   Field Number:
+
+    1) Time (UTC)
+    2) Status, V = Navigation receiver warning
+    3) Latitude
+    4) N or S
+    5) Longitude
+    6) E or W
+    7) Speed over ground, knots
+    8) Track made good, degrees true
+    9) Date, ddmmyy
+    10) Magnetic Variation, degrees
+    11) E or W
+    12) Checksum
+*/
+exports.TYPE = 'nav-info';
+exports.ID = 'RMC';
+
+exports.decode = function(fields) {
+  return {
+    sentence: exports.ID,
+    type: exports.TYPE,
+    timestamp: fields[1],
+    status: fields[2] == 'V' ? 'warning' : 'valid',
+    lat: fields[3],
+    latPole: fields[4],
+    lon: fields[5],
+    lonPole: fields[6],
+    speedKnots: +fields[7],
+    trackTrue: +fields[8],
+    date: fields[9],
+    variation: +fields[10],
+    variationPole: fields[11]
+  };
+}