Initialer Commit: Kundenverwaltung (PHP/Smarty)

Bestehende Codebasis als Ausgangsstand aufgenommen.

- .gitignore: Kundendaten (uploads_*), Smarty-Compile-Cache
  (templates_c), Laufzeit-Temp und Datenbank-Dumps ausgeschlossen;
  Verzeichnisstruktur ueber .gitkeep erhalten
- .gitattributes: Zeilenenden normalisiert (LF im Repo),
  Binaerformate markiert
- db-backup.php: MySQL-Zugangsdaten kommen jetzt wie im Rest der
  Anwendung aus der externen Konfiguration statt hartkodiert aus der
  Datei; Passwort wird ueber eine temporaere Optionsdatei statt per
  Kommandozeile uebergeben, Fehler von mysqldump/gzip werden gemeldet,
  Aufraeumen aelterer Backups berechnet Jahr und Monat konsistent

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

js/bumpbox/assets.js

@@ -0,0 +1,22 @@
+// MooTools: the javascript framework.
+// Load this file's selection again by visiting: http://mootools.net/more/417ab68a672f38ea1c04efab47af2ff7 
+// Or build this file again with packager using: packager build More/Assets
+/*
+---
+copyrights:
+  - [MooTools](http://mootools.net)
+
+licenses:
+  - [MIT License](http://mootools.net/license.txt)
+...
+*/
+MooTools.More={version:"1.4.0.1",build:"a4244edf2aa97ac8a196fc96082dd35af1abab87"};var Asset={javascript:function(d,b){if(!b){b={};}var a=new Element("script",{src:d,type:"text/javascript"}),e=b.document||document,c=b.onload||b.onLoad;
+delete b.onload;delete b.onLoad;delete b.document;if(c){if(typeof a.onreadystatechange!="undefined"){a.addEvent("readystatechange",function(){if(["loaded","complete"].contains(this.readyState)){c.call(this);
+}});}else{a.addEvent("load",c);}}return a.set(b).inject(e.head);},css:function(d,a){if(!a){a={};}var b=new Element("link",{rel:"stylesheet",media:"screen",type:"text/css",href:d});
+var c=a.onload||a.onLoad,e=a.document||document;delete a.onload;delete a.onLoad;delete a.document;if(c){b.addEvent("load",c);}return b.set(a).inject(e.head);
+},image:function(c,b){if(!b){b={};}var d=new Image(),a=document.id(d)||new Element("img");["load","abort","error"].each(function(e){var g="on"+e,f="on"+e.capitalize(),h=b[g]||b[f]||function(){};
+delete b[f];delete b[g];d[g]=function(){if(!d){return;}if(!a.parentNode){a.width=d.width;a.height=d.height;}d=d.onload=d.onabort=d.onerror=null;h.delay(1,a,a);
+a.fireEvent(e,a,1);};});d.src=a.src=c;if(d&&d.complete){d.onload.delay(1);}return a.set(b);},images:function(c,b){c=Array.from(c);var d=function(){},a=0;
+b=Object.merge({onComplete:d,onProgress:d,onError:d,properties:{}},b);return new Elements(c.map(function(f,e){return Asset.image(f,Object.append(b.properties,{onload:function(){a++;
+b.onProgress.call(this,a,e,f);if(a==c.length){b.onComplete();}},onerror:function(){a++;b.onError.call(this,a,e,f);if(a==c.length){b.onComplete();}}}));
+}));}};