feat(face): idle-task sync, weather, health widgets, battery estimator v2

AppMessage transport (face ↔ pkjs ↔ mock Task API) validated end-to-end:
- GameSnapshot full-field inbox handler (13 protocol keys)
- serverDown signaling; oxblood "!" indicator on task strip, gated by
  strip visibility (ASCII placeholder; PDC later)
- requestSync watch→phone wake on launch (deferred 300ms send)
- inbox_dropped/outbox_failed diagnostics; 256-byte inbox
- pkjs: timeout-guarded single-callback XHR; dictionary cache with
  version compare; last-good weather resend (fail-dead-silent)

Widgets:
- W_HEART: 1-min avg BPM, state-colored H marker (green=reading,
  oxblood=no signal), HealthServiceTimeScope API per SDK 4.33
- S/D placeholders for steps/distance; WB battery with PDC-pending icon
- Weather: NWS primary / Open-Meteo fallback, CONUS geo auto-switch,
  cond/temp/hi-lo packet, ASCII condition glyph. Wire unit °F;
  metric toggle deferred to settings (render-time conversion, DESIGN §5)
- Battery estimator: hours-based regression, 5% power-save floor,
  ~Nd / ~Nh under 24h display; DEV_BATT_TEST sample injection

Layout: LAYOUT_VERSION 3 (W_HEART appended; version-gated regeneration).
Known: emoji in FROZEN strip replaced with plain dash; battery modes
(BAT_PERCENT/DAYS/BOTH) parsed but renderer honors BAT_BOTH only.

Refs: PROTOCOL.md v3.0 §9 build order items 2-4; DESIGN.md Laws 5/6.

nine-hazes-face/package.json

@@ -17,7 +17,8 @@
     },
     "messageKeys": ["taskName", "syncTime", "clockOff", "boundSec", "used",
                     "taskCount", "curType", "curRem", "status", "abortCode",
-                    "pendItems", "pendXp", "dictV", "serverDown", "requestSync"],
+                    "pendItems", "pendXp", "dictV", "serverDown", "requestSync",
+                    "weatherTemp", "weatherHi", "weatherLo", "weatherTs", "weatherCond"],
     "resources": {
       "media": []
     }

nine-hazes-face/src/c/nine-hazes-face.c

@@ -20,6 +20,10 @@ static bool    s_health_ok = false;
 static int     s_bat_pct = -1;
 static bool    s_server_down = false;   // set by serverDown tuple, cleared on good sync
 
+static char    s_weather[16];
+static int16_t s_wx_temp = INT16_MIN, s_wx_hi = INT16_MIN, s_wx_lo = INT16_MIN;
+static uint8_t s_wx_cond = 0;
+
 // ---- battery estimator ------------------------------------------------------
 #define BAT_SAMPLES_MAX 16
 #define BAT_KEY 102
@@ -147,6 +151,13 @@ static void update_values(void) {
   else if (s->status == 3)  snprintf(s_strip, sizeof(s_strip), "ABORTED (%d)", s->abort_code);
   else if (s->status == 4)  snprintf(s_strip, sizeof(s_strip), "LOCKED");
   else                      snprintf(s_strip, sizeof(s_strip), "No hero yet");
+  if (s_wx_temp != INT16_MIN) {
+    static const char wx_icon[8] = { '?', 'o', '~', 'C', 'F', 'R', '*', 'T' };
+    snprintf(s_weather, sizeof(s_weather), "%c %d° %d/%d",
+             wx_icon[s_wx_cond & 7], s_wx_temp, s_wx_hi, s_wx_lo);
+  } else {
+    snprintf(s_weather, sizeof(s_weather), "--/--");
+  }
 }
 
 // ---- renderer -------------------------------------------------------------------
@@ -206,7 +217,7 @@ static void canvas_update(Layer *layer, GContext *ctx) {
         break;
       }
       case W_SLEEP:         text = s_sleep;       break;
-      case W_WEATHER:       text = "--/--";       break;
+      case W_WEATHER:       text = s_weather;      break;
       case W_OMEN:          text = "";            break;
       case W_HEART: {
         // state-indicating marker: moss = reading, oxblood = no signal
@@ -261,7 +272,7 @@ static void layout_default(void) {
     {W_STEPS,          1, 4, 115, 0, PAL_TEXT,     0},
     {W_DISTANCE,       1, 64,115, 0, PAL_TEXT,     0},
     {W_HEART,          1, 122, 115, 0, PAL_TEXT,   0},
-    {W_WEATHER,        0, 4, 130, 2, PAL_TEXT,     0},
+    {W_WEATHER,        1, 4, 130, 2, PAL_TEXT,     0},
     {W_OMEN,           0, 4, 150, 0, PAL_POSITIVE, 0},
     {W_SLEEP,          0, 4, 170, 1, PAL_WATER,    0},
     {W_TASK_STRIP,     1, 0, 172, 1, PAL_ACCENT,   0},
@@ -338,6 +349,10 @@ static void inbox_received(DictionaryIterator *iter, void *ctx) {
     taskname_store(name);
   }
 
+  if ((t = dict_find(iter, MESSAGE_KEY_weatherTemp))) s_wx_temp = t->value->int16;
+  if ((t = dict_find(iter, MESSAGE_KEY_weatherHi)))   s_wx_hi   = t->value->int16;
+  if ((t = dict_find(iter, MESSAGE_KEY_weatherLo)))   s_wx_lo   = t->value->int16;
+
   s_server_down = false;    // a good sync clears the flag
   APP_LOG(APP_LOG_LEVEL_DEBUG, "[MSG] snapshot ok: st=%u used=%u rem=%u",
           s.status, s.used, s.cur_rem);

nine-hazes-face/src/pkjs/index.js

@@ -38,6 +38,139 @@ function get(path, cb) {
     xhr.send();
 }
 
+// ---- weather (NWS default, Open-Meteo fallback, geo auto-switch) -----------
+// Temperature unit on the wire: Fahrenheit. (Unit toggle arrives with the
+// settings page; render-time conversion then, per DESIGN §5.)
+
+var WX_COORD_TTL = 30 * 60 * 1000;   // refix location at most every 30 min
+
+function getURL(url, cb) {
+    var xhr = new XMLHttpRequest();
+    var done = false;
+    var abortTimer = setTimeout(function () {
+        if (done) return;
+        done = true;
+        cb('timeout');
+        try { xhr.abort(); } catch (e) {}
+    }, 7000);
+    xhr.open('GET', url, true);
+    xhr.onload = function () {
+        if (done) return;
+        done = true;
+        clearTimeout(abortTimer);
+        if (xhr.status !== 200) return cb('HTTP ' + xhr.status);
+        try { cb(null, JSON.parse(xhr.responseText)); }
+        catch (e) { cb('malformed'); }
+    };
+    xhr.onerror = function () {
+        if (done) return;
+        done = true;
+        clearTimeout(abortTimer);
+        cb('network');
+    };
+    xhr.send();
+}
+
+function fetchWeather(cb) {
+    var coords = null;
+    try { coords = JSON.parse(localStorage.getItem('wx_coords') || 'null'); } catch (e) {}
+    if (coords && (Date.now() - coords.ts) < WX_COORD_TTL) {
+        return wxLookup(coords.lat, coords.lon, cb);
+    }
+    if (typeof navigator === 'undefined' || !navigator.geolocation) {
+        return coords ? wxLookup(coords.lat, coords.lon, cb) : cb(null);
+    }
+    navigator.geolocation.getCurrentPosition(function (pos) {
+        var lat = pos.coords.latitude, lon = pos.coords.longitude;
+        localStorage.setItem('wx_coords',
+                             JSON.stringify({ ts: Date.now(), lat: lat, lon: lon }));
+        wxLookup(lat, lon, cb);
+    }, function () {
+        // fix failed: fall back to stale coords or nothing
+        if (coords) return wxLookup(coords.lat, coords.lon, cb);
+        cb(null);
+    }, { timeout: 8000, maximumAge: 600000 });
+}
+
+function wxLookup(lat, lon, cb) {
+    // rough US bbox (CONUS + AK + HI + PR): NWS has data, else Open-Meteo
+    var inUS = (lat >= 17 && lat <= 72 && lon >= -179 && lon <= -66);
+    if (inUS) return nwsFetch(lat, lon, cb);
+    openMeteoFetch(lat, lon, cb);
+}
+
+function nwsFetch(lat, lon, cb) {
+    // step 1: resolve grid point
+    getURL('https://api.weather.gov/points/' + lat.toFixed(4) + ',' + lon.toFixed(4),
+           function (err, p) {
+               if (err || !p || !p.properties || !p.properties.forecast) {
+                   return openMeteoFetch(lat, lon, cb);   // fallback ladder
+               }
+               // step 2: pull forecast periods
+               getURL(p.properties.forecast, function (ferr, f) {
+                   if (ferr || !f || !f.properties || !f.properties.periods) {
+                       return openMeteoFetch(lat, lon, cb);
+                   }
+                   var periods = f.properties.periods;
+                   var now = periods[0];
+                   var cond = nwsCond(now.shortForecast);
+                   if (!now) return cb(null);
+                   var unitC = (now.temperatureUnit === 'C');
+                   var conv = function (v, c) { return c ? Math.round(v * 9 / 5 + 32) : Math.round(v); };
+                   var temp = conv(now.temperature, unitC);
+                   // hi/lo: today's daytime period and tonight's low
+                   var hi = temp, lo = temp, seenLo = false;
+                   for (var i = 0; i < periods.length && i < 4; i++) {
+                       var P = periods[i];
+                       var pu = (P.temperatureUnit === 'C');
+                       if (P.isDaytime) hi = conv(P.temperature, pu);
+                       else if (!seenLo) { lo = conv(P.temperature, pu); seenLo = true; }
+                   }
+                   cb({ temp: temp, hi: hi, lo: lo, cond: cond });
+               });
+           });
+}
+
+function openMeteoFetch(lat, lon, cb) {
+    var url = 'https://api.open-meteo.com/v1/forecast' +
+    '?latitude=' + lat.toFixed(4) + '&longitude=' + lon.toFixed(4) +
+    '&current=temperature_2m,weather_code&daily=temperature_2m_max,temperature_2m_min' +
+    '&temperature_unit=fahrenheit&forecast_days=1&timezone=auto';
+    getURL(url, function (err, w) {
+        if (err || !w || !w.current) return cb(null);
+        cb({
+            temp: Math.round(w.current.temperature_2m),
+           hi:   Math.round(w.daily.temperature_2m_max[0]),
+           lo:   Math.round(w.daily.temperature_2m_min[0]),
+           cond: wmoCond(w.current.weather_code)
+        });
+    });
+}
+
+function sendWeather() {
+    fetchWeather(function (wx) {
+        var payload;
+        if (wx) {
+            localStorage.setItem('wx_last',
+                                 JSON.stringify(wx));                  // last-good cache
+            payload = { weatherTemp: wx.temp, weatherHi: wx.hi,
+                weatherLo: wx.lo, weatherCond: wx.cond,
+                weatherTs: Math.floor(Date.now() / 1000) };
+        } else {
+            // fail-dead-silent: resend last-good if we have one
+            try {
+                var last = JSON.parse(localStorage.getItem('wx_last') || 'null');
+                if (last) payload = { weatherTemp: last.temp, weatherHi: last.hi,
+                    weatherLo: last.lo,
+                    weatherTs: Math.floor(Date.now() / 1000) };
+            } catch (e) {}
+        }
+        if (payload) Pebble.sendAppMessage(payload,
+            function () { console.log('[PKJS] weather delivered'); },
+                                           function (e) { console.log('[PKJS] weather send failed'); });
+    });
+}
+
 // dictionary: names indexed by task id, cached
 function dictNames(cb) {
     var cachedV = parseInt(localStorage.getItem('dict_v') || '-1', 10);
@@ -141,6 +274,7 @@ function sync() {
                     Pebble.sendAppMessage({ serverDown: 1 }, function(){}, function(){});
                 }
             );
+            sendWeather();   // fire-and-forget; separate message
         };
 
         if (cachedV === q.dict) {
@@ -182,3 +316,30 @@ function statusCode(s) {
     var map = { 'EMPTY': 0, 'RUNNING': 1, 'FROZEN': 2, 'ABORTED': 3, 'LOCKED': 4 };
     return map[s] !== undefined ? map[s] : 0;
 }
+
+// weather condition → normalized code (0 unk,1 clear,2 pcloudy,3 cloudy,
+// 4 fog,5 rain,6 snow,7 tstorm); PDC icons map 1:1 later
+function nwsCond(text) {
+    if (!text) return 0;
+    var t = String(text).toLowerCase();
+    if (t.indexOf('thunder') >= 0) return 7;
+    if (t.indexOf('snow') >= 0 || t.indexOf('sleet') >= 0) return 6;
+    if (t.indexOf('rain') >= 0 || t.indexOf('shower') >= 0 ||
+        t.indexOf('drizzle') >= 0) return 5;
+    if (t.indexOf('fog') >= 0 || t.indexOf('haze') >= 0) return 4;
+    if (t.indexOf('partly') >= 0 || t.indexOf('mostly sunny') >= 0) return 2;
+    if (t.indexOf('cloud') >= 0 || t.indexOf('overcast') >= 0) return 3;
+    if (t.indexOf('sun') >= 0 || t.indexOf('clear') >= 0) return 1;
+    return 0;
+}
+
+function wmoCond(code) {
+    if (code === 0) return 1;                    // clear
+    if (code === 1 || code === 2) return 2;      // mainly/partly clear
+    if (code === 3) return 3;                    // overcast
+    if (code === 45 || code === 48) return 4;    // fog
+    if ((code >= 51 && code <= 67) || (code >= 80 && code <= 82)) return 5;
+    if ((code >= 71 && code <= 77) || code === 85 || code === 86) return 6;
+    if (code >= 95) return 7;                    // thunder
+    return 0;
+}