fix(analytics): use working Mixpanel SDK URL; drop Rybbit

The deployed snippet loaded //cdn.mxpnl.com/libs/mixpanel-js/2.56.0/mixpanel.gsl.js,
which 404s — so the SDK never loaded and no events were ever sent (zero data in
the dashboard). Switch to the official cdn URL (mixpanel-2-latest.min.js, HTTP 200).

Rybbit was already removed on main; confirmed no residue remains in the tree.

Author: rosuH

site/index.html

@@ -205,7 +205,7 @@
 </style>
 <!-- Mixpanel analytics. The project token is public by design (same as GA/Plausible) — it only identifies which project events belong to; it grants no read access to dashboard data. -->
 <script>
-(function(f,b){if(!b.__SV){var e,g,i,h;window.mixpanel=b;b._i=[];b.init=function(a,e,d){function f(b){var c=b.split(".");2==c.length&&(b=b[c[0]],a[c[0]]=a[c[0]]||{},a=a[c[0]])}b._q.push({a:d});f("track");f("identify");f("reset");f("register");f("alias");f("people.set");f("people.increment");f("track_charge");f("append");b._i[d]={};a&&"function"==typeof a&&(b._i[d]=a)};b.__SV=1.2;e=f.createElement("script");e.type="text/javascript";e.async=!0;e.src="https://cdn.mxpnl.com/libs/mixpanel-js/2.56.0/mixpanel.gsl.js";e.crossOrigin="anonymous";g=f.getElementsByTagName("script")[0];g.parentNode.insertBefore(e,g)}})(document,window.mixpanel||[]);
+(function(f,b){if(!b.__SV){var e,g,i,h;window.mixpanel=b;b._i=[];b.init=function(a,e,d){function f(b){var c=b.split(".");2==c.length&&(b=b[c[0]],a[c[0]]=a[c[0]]||{},a=a[c[0]])}b._q.push({a:d});f("track");f("identify");f("reset");f("register");f("alias");f("people.set");f("people.increment");f("track_charge");f("append");b._i[d]={};a&&"function"==typeof a&&(b._i[d]=a)};b.__SV=1.2;e=f.createElement("script");e.type="text/javascript";e.async=!0;e.src="https://cdn.mxpnl.com/libs/mixpanel-2-latest.min.js";g=f.getElementsByTagName("script")[0];g.parentNode.insertBefore(e,g)}})(document,window.mixpanel||[]);
 mixpanel.init("72970b4dccaded033cafffc4bb48e196", { debug: false, track_pageview: true, persistence: "localStorage" });
 </script>
 </head>

web/index.html

@@ -205,7 +205,7 @@
 </style>
 <!-- Mixpanel analytics. The project token is public by design (same as GA/Plausible) — it only identifies which project events belong to; it grants no read access to dashboard data. -->
 <script>
-(function(f,b){if(!b.__SV){var e,g,i,h;window.mixpanel=b;b._i=[];b.init=function(a,e,d){function f(b){var c=b.split(".");2==c.length&&(b=b[c[0]],a[c[0]]=a[c[0]]||{},a=a[c[0]])}b._q.push({a:d});f("track");f("identify");f("reset");f("register");f("alias");f("people.set");f("people.increment");f("track_charge");f("append");b._i[d]={};a&&"function"==typeof a&&(b._i[d]=a)};b.__SV=1.2;e=f.createElement("script");e.type="text/javascript";e.async=!0;e.src="https://cdn.mxpnl.com/libs/mixpanel-js/2.56.0/mixpanel.gsl.js";e.crossOrigin="anonymous";g=f.getElementsByTagName("script")[0];g.parentNode.insertBefore(e,g)}})(document,window.mixpanel||[]);
+(function(f,b){if(!b.__SV){var e,g,i,h;window.mixpanel=b;b._i=[];b.init=function(a,e,d){function f(b){var c=b.split(".");2==c.length&&(b=b[c[0]],a[c[0]]=a[c[0]]||{},a=a[c[0]])}b._q.push({a:d});f("track");f("identify");f("reset");f("register");f("alias");f("people.set");f("people.increment");f("track_charge");f("append");b._i[d]={};a&&"function"==typeof a&&(b._i[d]=a)};b.__SV=1.2;e=f.createElement("script");e.type="text/javascript";e.async=!0;e.src="https://cdn.mxpnl.com/libs/mixpanel-2-latest.min.js";g=f.getElementsByTagName("script")[0];g.parentNode.insertBefore(e,g)}})(document,window.mixpanel||[]);
 mixpanel.init("72970b4dccaded033cafffc4bb48e196", { debug: false, track_pageview: true, persistence: "localStorage" });
 </script>
 </head>