Bump Markdig from 0.45.0 to 1.0.0 (#2763)

---
updated-dependencies:
- dependency-name: Markdig
  dependency-version: 1.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Directory.Packages.props

@@ -75,7 +75,7 @@
     <PackageVersion Include="Github.Actions.Core" Version="9.0.0" />
     <PackageVersion Include="Microsoft.Extensions.Logging" Version="10.0.0" />
     <PackageVersion Include="Microsoft.Extensions.Logging.Console" Version="10.0.0" />
-    <PackageVersion Include="Markdig" Version="0.45.0" />
+    <PackageVersion Include="Markdig" Version="1.0.0" />
     <PackageVersion Include="ModelContextProtocol" Version="0.2.0-preview.1" />
     <PackageVersion Include="ModelContextProtocol.AspNetCore" Version="0.2.0-preview.1" />
     <PackageVersion Include="NetEscapades.EnumGenerators" Version="1.0.0-beta12" PrivateAssets="all" ExcludeAssets="runtime" />