fix(install): split windows workflow

DONE.md

@@ -24,6 +24,8 @@
   - Normalized PowerShell here-strings to prevent parse errors during installation.
 - ✅ **Go auto-install on Windows**
   - Removed the Go prompt in `install.sh`; missing Go is now installed automatically.
+- ✅ **Windows install workflow split**
+  - `install.sh` now delegates to the Windows installer to avoid mixed-shell prompts.
 
 ## Version 0.1.0-dev25 (2026-01-22) - Settings Preferences Expansion
 

TODO.md

@@ -10,6 +10,8 @@ This file tracks upcoming features, improvements, and known issues.
   - Normalize PowerShell here-strings to prevent parser errors.
 - [X] **Go auto-install in install.sh**
   - Skip prompting for Go and install automatically when missing.
+- [X] **Windows install workflow split**
+  - Route Windows to the dedicated installer to avoid mixed-shell prompts.
 
 ## Documentation: Fix Structural Errors
 

docs/INSTALL_WINDOWS.md

@@ -27,6 +27,8 @@ If you haven't already, download the project files as a ZIP and extract them to
 
 Once the script finishes, you can run the application by double-clicking `run.bat` in the main project folder.
 
+> **Note:** On Windows, use `setup-windows.bat` instead of `scripts/install.sh` to avoid mixed-shell prompts.
+
 ---
 
 ## Method 2: Manual Installation

scripts/install.sh

@@ -103,6 +103,17 @@ echo "  $INSTALL_TITLE"
 echo "════════════════════════════════════════════════════════════════"
 echo ""
 
+# Windows uses a dedicated installer to avoid Git Bash/PowerShell chaining.
+if [ "$IS_WINDOWS" = true ]; then
+    if command -v powershell.exe &> /dev/null; then
+        powershell.exe -NoProfile -ExecutionPolicy Bypass -File "$PROJECT_ROOT/scripts/install-deps-windows.ps1"
+        exit $?
+    fi
+    echo -e "${RED}[ERROR]${NC} powershell.exe not found."
+    echo "Please run: $PROJECT_ROOT\\scripts\\setup-windows.bat"
+    exit 1
+fi
+
 # Step 1: Check if Go is installed
 echo -e "${CYAN}[1/2]${NC} Checking Go installation..."
 if ! command -v go &> /dev/null; then
@@ -110,9 +121,7 @@ if ! command -v go &> /dev/null; then
     echo "Installing Go..."
     install_go=false
 
-    if [ "$IS_WINDOWS" = true ]; then
-        echo "Go will be installed by the Windows dependency installer."
-    elif [ "$IS_DARWIN" = true ]; then
+    if [ "$IS_DARWIN" = true ]; then
         if command -v brew &> /dev/null; then
             brew install go
             install_go=true