feat: mailing to filtered teamer list

addresses #869dv9bur

templates/admin/teamer/_mailing_skipped.html.twig

@@ -0,0 +1,33 @@
+{#- the reasons are prepositional phrases on purpose: an attributive adjective would have to
+    agree in number and gender ("1 gelöschte:r" / "2 gelöschte"), which reads badly next to
+    the gender neutral Teamer:innen and is not worth inflecting for a status line -#}
+{%- set reasons = [] -%}
+{%- if recipients.skippedNoEmail > 0 -%}
+    {%- set reasons = reasons|merge([{ 'count': recipients.skippedNoEmail, 'phrase': 'ohne E-Mail-Adresse' }]) -%}
+{%- endif -%}
+{%- if recipients.skippedDeleted > 0 -%}
+    {%- set reasons = reasons|merge([{ 'count': recipients.skippedDeleted, 'phrase': 'mit gelöschtem Account' }]) -%}
+{%- endif -%}
+{%- if recipients.skippedDisabled > 0 -%}
+    {%- set reasons = reasons|merge([{ 'count': recipients.skippedDisabled, 'phrase': 'mit gesperrtem Account' }]) -%}
+{%- endif -%}
+
+{%- set noun = recipients.skippedCount == 1 ? 'Teamer:in' : 'Teamer:innen' -%}
+{%- set verb = recipients.skippedCount == 1 ? 'wird' : 'werden' -%}
+
+{%- if reasons|length == 1 -%}
+    {#- one reason carries the whole count, so it reads as a single sentence -#}
+    {{- '%d %s %s %s übersprungen'|format(recipients.skippedCount, noun, reasons|first.phrase, verb) -}}
+{%- else -%}
+    {%- set parts = [] -%}
+    {%- for reason in reasons -%}
+        {%- set parts = parts|merge(['%d %s'|format(reason.count, reason.phrase)]) -%}
+    {%- endfor -%}
+    {{- '%d %s %s übersprungen: %s und %s'|format(
+        recipients.skippedCount,
+        noun,
+        verb,
+        parts|slice(0, parts|length - 1)|join(', '),
+        parts|last
+    ) -}}
+{%- endif -%}