chore: bump version to 1.4.5

Manifest sync across csproj, yaml, repo.json, README, CHANGELOG,
ROADMAP and the Plugin.cs schema-gate error message. ROADMAP also gets
the v1.4.4 release block that was missed in that cycle's closure.

Forge-post v1.4.5.md follows the established frontmatter + DE-body
convention; the EN block is sourced from the yaml changelog by the
forge-announce workflow.

HellionChat/Plugin.cs

@@ -159,8 +159,8 @@ public sealed class Plugin : IAsyncDalamudPlugin
         if (Config.Version < 16)
         {
             throw new InvalidOperationException(
-                $"HellionChat v1.4.4 requires config schema v16, got v{Config.Version}. "
-                    + "Please install v1.4.2 first to migrate the configuration, then upgrade to v1.4.4."
+                $"HellionChat v1.4.5 requires config schema v16, got v{Config.Version}. "
+                    + "Please install v1.4.2 first to migrate the configuration, then upgrade to v1.4.5."
             );
         }