Fix Windows CI builds by downgrading rsmpeg for FFmpeg 6.x compatibility

Add PowerShell steps to Windows CI workflows to temporarily downgrade
rsmpeg from 0.18.0 (FFmpeg 8.0) to 0.14.2 (FFmpeg 6.1) since vcpkg
provides an older FFmpeg version.

This matches the Linux CI fix and ensures all CI platforms can build
successfully while maintaining FFmpeg 8.0 support for local development.

Author: prateekmedia

.github/workflows/build_windows.yml

@@ -58,6 +58,10 @@ jobs:
           override: true
       - name: Install Win 10 SDK
         uses: ilammy/msvc-dev-cmd@v1
+      - name: Downgrade rsmpeg for FFmpeg 6.x compatibility
+        shell: powershell
+        run: |
+          (Get-Content src\rust\Cargo.toml) -replace 'rsmpeg = \{ version = "0.18.0\+ffmpeg.8.0"', 'rsmpeg = { version = "0.14.2+ffmpeg.6.1"' | Set-Content src\rust\Cargo.toml
       - name: build Release-Full
         env:
           LIBCLANG_PATH: "C:\\Program Files\\LLVM\\lib"
@@ -109,6 +113,10 @@ jobs:
           override: true
       - name: Install Win 10 SDK
         uses: ilammy/msvc-dev-cmd@v1
+      - name: Downgrade rsmpeg for FFmpeg 6.x compatibility
+        shell: powershell
+        run: |
+          (Get-Content src\rust\Cargo.toml) -replace 'rsmpeg = \{ version = "0.18.0\+ffmpeg.8.0"', 'rsmpeg = { version = "0.14.2+ffmpeg.6.1"' | Set-Content src\rust\Cargo.toml
       - name: build Debug-Full
         env:
           LIBCLANG_PATH: "C:\\Program Files\\LLVM\\lib"