fix(desktop): resolve electronDist to the actual electron install location (#48081)

After the June lockfile regeneration (#46652) floated electron and reshuffled
npm workspace hoisting, the desktop pack fails with "The specified electronDist
does not exist". apps/desktop/package.json pointed electronDist at the repo
root (../../node_modules/electron/dist) while npm now installs electron nested
under apps/desktop/node_modules/electron. The two contradict, so a clean
install can never package the app (Windows + macOS).

- electronDist -> node_modules/electron/dist (resolved relative to apps/desktop,
  i.e. the workspace-local install npm actually produces).
- hermes_cli/main.py, scripts/install.sh, scripts/install.ps1: add a runtime
  electron-dir resolver that prefers apps/desktop/node_modules/electron and
  falls back to the root hoist, so dist checks + the mirror re-download work
  under either npm layout.
- patch-electron-builder-mac-binary.cjs: try the workspace-local Electron.app
  before the root hoist in the macOS binary-restore fallback (sibling site no
  PR touched).
- test: assert build.electronDist resolves to where the lockfile installs
  electron, so a future hoist change (root <-> nested) can't silently break it.

Salvages the overlapping work in #48003 (sitkarev), #48012 (omegazheng), and
#48033 (james47kjv).

Co-authored-by: sitkarev <59806492+sitkarev@users.noreply.github.com>
Co-authored-by: omegazheng <zheng@omegasys.eu>
Co-authored-by: james47kjv <220877172+james47kjv@users.noreply.github.com>

apps/desktop/scripts/patch-electron-builder-mac-binary.cjs

@@ -24,6 +24,11 @@ const replacement = `    // ${marker}: electron-builder 26.8.x can sometimes cop
     if (!fs.existsSync(bundledElectronBinary)) {
         const candidates = [
             path.join(packager.info.framework.distMacOsAppName, "Contents", "MacOS", electronBranding.productName),
+            // npm may nest the workspace-only electron devDep under
+            // apps/desktop/node_modules (process.cwd() during pack), or hoist
+            // it to the repo root. Try the workspace-local install first, then
+            // the root hoist, so the fallback works under either layout.
+            path.join(process.cwd(), "node_modules", "electron", "dist", "Electron.app", "Contents", "MacOS", electronBranding.productName),
             path.join(process.cwd(), "..", "..", "node_modules", "electron", "dist", "Electron.app", "Contents", "MacOS", electronBranding.productName),
         ];
         const sourceBinary = candidates.find(candidate => fs.existsSync(candidate));