feat(packaging): a Light installer target with no bundled node runtime

MeshBay Light ships the Electron client + UI only -- no PyInstaller node
freeze, no ffmpeg, no service install/autostart. Two standalone
electron-builder configs (Full via package.json's build field, Light via
electron-builder.light.yml passed with --config, which reads only that
file -- confirmed against app-builder-lib's own config loader) rather than
one config branching on a flag.

build-win-common.ps1 holds the steps both orchestrators share (Node check,
npm ci, Electron bump, sync-ui) so build-win.ps1 (Full) and the new
build-win-light.ps1 cannot drift apart; build-win.ps1 is refactored to
dot-source it with no behavior change (rebuilt and diffed byte-identical
output).

installer-light.nsh keeps the one thing Light still needs -- an
unconditional firewall rule, since the client listens too -- and none of
the service-mode/autostart machinery installer.nsh carries, which has
nothing to gate without a bundled node.

dist-light/ (Light's own electron-builder output dir) gets its own
.gitignore line since the bare dist/ rule does not match it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/packaging/win/build-win-light.ps1 b/packaging/win/build-win-light.ps1
new file mode 100644
index 0000000..5a8a06e
--- /dev/null
+++ b/packaging/win/build-win-light.ps1
@@ -0,0 +1,85 @@
+<#
+.SYNOPSIS
+    Build the Windows "Light" installer: Electron client + UI only, no
+    bundled node.
+
+.DESCRIPTION
+    The counterpart of build-win.ps1 (Full) for anyone who only wants to
+    *use* MeshBay -- join groups, chat, browse, download, stream, cast --
+    without ever hosting content from this machine. See
+    C:\Users\admin\devel\light-client.md for the evaluation this
+    implements: a member never needs a local node to begin with (identity
+    keys are per node -- the *host's* node, not the joiner's), so Light is
+    the existing browser-only usage pattern wrapped in the Electron shell,
+    minus the frozen meshbay-node.exe / ffmpeg / autostart bundle.
+
+    Steps 1-4 are identical to build-win.ps1 (build-win-common.ps1). Step 5,
+    PyInstaller freezing a node runtime, does not happen at all -- that is
+    the entire point of this target. Step 6 hands electron-builder a
+    standalone config (electron-builder.light.yml) instead of package.json's
+    `build` field: passing --config makes electron-builder read ONLY that
+    file (see app-builder-lib/out/util/config/load.js's getConfig -- when a
+    config path is given, package.json's own `build` field is never loaded,
+    so there is no array-merge ambiguity to worry about between the two
+    targets' very different extraResources).
+
+    Output: packages/meshbay-client/dist-light/MeshBay Light-Setup-<version>.exe
+    (a different output directory from Full's dist/, so the two builds never
+    race on the same files).
+
+.PARAMETER NoElectronBump
+    Keep the pinned Electron instead of upgrading to the latest release.
+#>
+[CmdletBinding()]
+param(
+    [switch]$NoElectronBump
+)
+
+$ErrorActionPreference = "Stop"
+Set-StrictMode -Version Latest
+
+$WinDir  = $PSScriptRoot
+$Repo    = (Resolve-Path (Join-Path $WinDir "..\..")).Path
+$Client  = Join-Path $Repo "packages\meshbay-client"
+$Config  = Join-Path $WinDir "electron-builder.light.yml"
+
+. (Join-Path $WinDir "build-win-common.ps1")
+
+if (-not (Test-Path $Config)) { throw "missing $Config" }
+
+# --- 1. Node -------------------------------------------------------------
+Assert-NodeVersion
+
+Push-Location $Client
+try {
+    # --- 2. deps ------------------------------------------------------
+    Invoke-NpmCi
+
+    # --- 3. Electron: build against the latest release --------------
+    Invoke-ElectronBump -NoElectronBump:$NoElectronBump -WinDir $WinDir
+
+    # --- 4. UI -----------------------------------------------------
+    Invoke-SyncUi
+
+    # --- 5. (no node runtime -- that is what makes this "Light") -----
+
+    # --- 6. installer ---------------------------------------
+    Step "electron-builder --win nsis --config electron-builder.light.yml"
+    & npx electron-builder --win nsis --config $Config
+    if ($LASTEXITCODE -ne 0) { throw "electron-builder failed" }
+}
+finally {
+    Pop-Location
+}
+
+$setup = Get-ChildItem (Join-Path $Client "dist-light") -Filter "*Setup*.exe" -ErrorAction SilentlyContinue |
+    Sort-Object LastWriteTime | Select-Object -Last 1
+Write-Host ""
+if ($setup) {
+    Write-Host "OK  installer: $($setup.FullName)" -ForegroundColor Green
+    Write-Host ("    ({0:N0} MB)" -f ($setup.Length / 1MB))
+}
+else {
+    Write-Host "!!  no *Setup*.exe found in $Client\dist-light" -ForegroundColor Red
+    exit 1
+}