Refactor unsafe collections and improve memory handling

Refactored enumerators across multiple unsafe collections to use
`ref` returns for `Current`, improving performance and reducing
memory usage. Enhanced memory management with `AllocationOption`
support and optimized resizing logic for collections like
`UnsafeBitSet`, `UnsafeSlotMap`, and `UnsafeSparseSet`.

Updated `publish-nuget.yaml` to support manual workflow dispatch
and trigger on `push`/`pull_request` events. Incremented project
version to `1.1.2` and ensured NuGet package generation on build.

.gitea/workflows/publish-nuget.yaml

@@ -1,9 +1,6 @@
 name: Publish NuGet Packages
 
 on:
-  push:
-    branches:
-      - main
   pull_request:
     branches:
       - main