feat(app): add 'Open with OpenCode' option to Windows context menu for folders

[alexyaroshuk]

Issue for this PR

Closes #15530

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Adds "Open with OpenCode" to Windows Explorer right-click context menu when you right-click a folder. This launches Opencode app and creates project from this folder, or switches to it if this project has previously been added

How:

• NSIS hooks (windows/hooks.nsh): During install, writes registry keys to HKCU\Software\Classes\Directory\shell\OpenCode. This tells Explorer to show the menu option.
• Deep link: When clicked, launches app with opencode://open-project?directory=%V URL
• App handles deep link: The existing deep link handler parses this URL and opens the project
• Fix: Changed DeepLinkExt import to work on all Windows builds (not just debug)

How did you verify your code works?

manual test: made a release build on windows, compared context menu:
before : no option to open with opencode
after: has option to open with opencode: opens app, and creates new project at this location or switches to it if this project has already been added

Screenshots / recordings

not a ui change

Files changed

File	Change
packages/desktop/src-tauri/windows/hooks.nsh	Created - NSIS installer hooks for registry entries
packages/desktop/src-tauri/tauri.conf.json	added installerHooks config
packages/desktop/src-tauri/src/lib.rs	fixed DeepLinkExt import for release builds

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR