nvda

eeb6143a - Correctly register .nvda-addon file association on installation (#19419)

Correctly register .nvda-addon file association on installation (#19419) Fixes #19411 ### Summary of the issue: When installing 64-bit versions of NVDA for the first time, the `.nvda-addon` file association is not registered. ### Description of user facing changes: The file association is now registered, so users can activate NVDA add-on packages for installation from File Explorer. ### Description of developer facing changes: None ### Description of development approach: Corrected the value of `config.registry.RegistryKey.ADDON_EXT` to include the leading `.` in `.nvda-addon`. ### Testing strategy: 1. Created a self-signed build. 2. Installed it in a clean Windows 11 VM. 3. Copied an NVDA add-on package into the VM. 4. Activated the file from File Explorer and verified that NVDA asked me if I wanted to install the add-on. ### Known issues with pull request: None.