chore(ci): ignored Stimulsoft packages in Dependabot

Stimulsoft.Dashboards.Win and Stimulsoft.Reports.Wpf are pinned at
2022.1.2 because our license only covers that build. Without an
ignore rule, Dependabot kept opening upgrade PRs (most recently
#72: 2022.1.2 -> 2026.2.2) that must be declined every time.

* Pin is enforced in Directory.Packages.props with an inline
  German comment ("Version bleibt wegen Lizenz!") on the
  Stimulsoft package versions
* Ignore is applied to both sibling packages so neither one
  drifts ahead of the licensed version
* Why a full ignore rather than a version range: the license is
  specific to 2022.1.2, not a major-version window — any other
  version is out of scope

If the license is ever expanded, remove the ignore block and
let Dependabot resume normal updates.

Author: karlspace

.github/dependabot.yml

@@ -33,6 +33,12 @@ updates:
           - "FluentAssertions*"
           - "coverlet*"
           - "Moq*"
+    # License-pinned packages: do not update.
+    # Stimulsoft 2022.1.2 is the version covered by our license — see
+    # Directory.Packages.props ("Version bleibt wegen Lizenz!").
+    ignore:
+      - dependency-name: "Stimulsoft.Dashboards.Win"
+      - dependency-name: "Stimulsoft.Reports.Wpf"
 
   # GitHub Actions
   - package-ecosystem: "github-actions"