Fix some CI (windows + nasm, core-macro error) (#2676)

* Moves index.html creation until after wasm creation so the webserver doesn't prematurely serve the page
* sets up nasm for windows builds (to be superseded by Remove Dioxus CLI NASM dependency #2666 #2682)
* puts magnanis-cli-support in a blocking task to prevent threadlocking during sequential builds
* changes order of client/server builds such that the client is built before the server so the webserver doesn't prematurely serve invalid client code
* declobbers "serve" such that each project gets a different dir in the target folder
* uses nest_service instead of fallback so the router doesn't respond with fallback codes
* reincorporates doge's fix from Fix hot-reloading on Windows #2544

.github/workflows/main.yml

@@ -269,6 +269,10 @@ jobs:
           targets: ${{ matrix.platform.target }}
           components: rustfmt
 
+      - name: Install nasm for windows (tls)
+        if: ${{ matrix.platform.target == 'x86_64-pc-windows-msvc' }}
+        uses: ilammy/setup-nasm@v1
+
       - name: Install cross
         if: ${{ matrix.platform.cross == true }}