feat(installer): make the installer branding-icon dir configurable

build.ps1 hardcoded frontend/public for the MSI icon, which breaks apps whose
frontend carries no favicon.ico. Add an installer_branding_dir copier var
(default frontend/public) and use it for BrandingDir, so an app without a usable
frontend favicon can point it at a dir it owns (e.g. installer/) that holds
favicon.ico.

Author: zendern

copier.yml

@@ -196,6 +196,12 @@ installer_manufacturer:
     help: "What is the human-friendly manufacturer/company name to show in the MSI installer and Add/Remove Programs (e.g. Acme Corp)?"
     when: "{{ install_as_windows_service }}"
 
+installer_branding_dir:
+    type: str
+    help: "Directory (relative to the repo root) holding the installer icon favicon.ico. Frontend apps can use frontend/public; apps whose frontend has no favicon should point this at a dir they own (e.g. installer)."
+    default: "frontend/public"
+    when: "{{ install_as_windows_service }}"
+
 installer_upgrade_code:
     type: str
     help: "A fixed-for-life UpgradeCode GUID for this app's MSI (generate once, NEVER change it - it identifies upgrades across versions). Format: 8-4-4-4-12 hex, e.g. 3b9d1f6a-2c84-4e7b-9a1f-6d5c4b3a2e10."

template/{% if install_as_windows_service %}installer{% endif %}/build.ps1.jinja

@@ -81,8 +81,9 @@ $BuildDir = Join-Path $ScriptRoot 'build'
 $StagingDir = Join-Path $BuildDir 'staging'
 $DistDir = Join-Path $ScriptRoot 'dist'
 $WixDir = Join-Path $ScriptRoot 'wix'
-# Reuse the app's own favicon as the installer icon rather than duplicating it.
-$BrandingDir = Join-Path $RepoRoot 'frontend\public'
+# Directory (relative to the repo root) holding the installer icon; it must contain favicon.ico.
+# Frontend apps reuse frontend/public; apps without a frontend point this elsewhere (e.g. installer/).
+$BrandingDir = Join-Path $RepoRoot '{% endraw %}{{ installer_branding_dir | replace('/', '\\') }}{% raw %}'
 $LicenseRtf = Join-Path $ScriptRoot 'license.rtf'
 
 if (-not $Version) {