ci(windows): upload raw Hermes-Setup.exe, drop dead NSIS upload step

tauri.conf.json targets are [app, dmg, appimage] — no nsis/msi — so the
windows build never produces target/release/bundle/nsis/*.exe. The NSIS
upload step pointed at a path that does not exist and would fail/no-op.

Drop it. The raw exe (Cargo [[bin]] name = Hermes-Setup -> Hermes-Setup.exe)
is the real deliverable and is already uploaded by the following step. Also
correct the now-stale signing-step comment.

.github/workflows/build-windows-installer.yml

@@ -79,7 +79,7 @@ jobs:
           endpoint: ${{ vars.AZURE_SIGNING_ENDPOINT }}
           signing-account-name: ${{ vars.AZURE_SIGNING_ACCOUNT_NAME }}
           certificate-profile-name: ${{ vars.AZURE_SIGNING_CERTIFICATE_PROFILE }}
-          # Sign both the raw exe and the bundled NSIS installer.
+          # Sign the raw Hermes-Setup.exe (tauri emits the bare exe, no NSIS bundle).
           files-folder: ${{ github.workspace }}\apps\bootstrap-installer\src-tauri\target\release
           files-folder-filter: exe
           files-folder-recurse: true
@@ -87,12 +87,6 @@ jobs:
           timestamp-rfc3161: http://timestamp.acs.microsoft.com
           timestamp-digest: SHA256
 
-      - name: Upload NSIS installer
-        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
-        with:
-          name: Hermes-Setup-installer
-          path: apps/bootstrap-installer/src-tauri/target/release/bundle/nsis/*.exe
-
       - name: Upload raw exe
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
         with: