Let OpenWeather calls-per-minute limit cascade to orgs and users

Drop the descriptor Default of 60 so the global panel field can be left
blank. A non-blank global value sits at the top of the cascade and locks
every lower layer, so the fixed default made the per-minute limit
un-overridable by organizations and users. Blank now means "inherit";
the runtime still falls back to 60 when no layer sets a value, so the
usage gauge is unchanged. Update the descriptor help and the Settings
row copy to explain the inherit behavior.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

API Server/internal/plugins/builtin/openweather/openweather.go

@@ -160,8 +160,8 @@ func (p *Plugin) Descriptor() plugins.Descriptor {
 				Help: "Longitude used by the health probe and by calls that supply no location (−180…180)."},
 			{Key: "lang", Label: "Language", Type: "text",
 				Help: "Optional ISO language code for human-readable weather descriptions (e.g. en, pl, de). Leave blank for the API default."},
-			{Key: "callsPerMinute", Label: "Calls per minute limit", Type: "number", Default: "60",
+			{Key: "callsPerMinute", Label: "Calls per minute limit", Type: "number",
-				Help: "Your OpenWeather plan's per-minute call limit (the free tier is 60). Used only to gauge usage in the app — OpenWeather does not report remaining quota, so the app counts the calls it makes against this number."},
+				Help: "Your OpenWeather plan's per-minute call limit (the free tier is 60). Used only to gauge usage in the app — OpenWeather does not report remaining quota, so the app counts the calls it makes against this number. Leave blank to let each organization or user set their own limit; the app falls back to 60 when no layer sets one."},
 		},
 	}
 }

Web App/web/src/components/Settings.vue

@@ -1891,7 +1891,7 @@ onBeforeUnmount(() => {
             </Row>
 
             <!-- calls-per-minute limit (used only to gauge usage) -->
-            <Row title="Calls per minute limit" desc="Your plan's per-minute limit (free tier is 60). Only used to gauge app usage below." keywords="calls per minute limit rate quota plan usage">
+            <Row title="Calls per minute limit" desc="Your plan's per-minute limit (free tier is 60). Only used to gauge app usage below. Leave blank to inherit; the app falls back to 60." keywords="calls per minute limit rate quota plan usage">
               <template v-if="owLocked('callsPerMinute')">
                 <span class="inline-flex items-center gap-2 font-mono text-sm text-ink">
                   {{ owField('callsPerMinute').effective || '60' }}