fix(install-windows): ask before downloading models instead of offering Ctrl+C

Ctrl+C in PS 5.1 kills the whole script, so the advertised way to skip the
download was also the way to abort the install before its final steps. Now a
'Download them now? [Y/n]' prompt, so declining continues to the end. The
default-model seed moves above the pull - it only writes a settings row and was
being lost along with the download. A test forbids offering Ctrl+C again.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

install-windows.ps1

@@ -243,8 +243,28 @@ if ((Test-Path (Join-Path $LegacyStore "blobs")) -and
 $env:OLLAMA_MODELS = $ModelStore
 Write-OK "Model store: $ModelStore"
 
+# Pin it as the default chat model. Runs BEFORE the download because it only
+# writes a settings row - nothing here needs the model to be present on disk,
+# and putting it after the pull meant declining the download also lost it. Runs from the repo root so the synapse
+# package imports; only writes the 'model' setting in the shared DB.
+Write-Step "Setting $ChatModel as the default model"
+Push-Location $RepoRoot
+& $VenvPy -c "from synapse.memory.store import store; from synapse.nexus_config import DEFAULT_CHAT_MODEL; store.update_settings({'model': DEFAULT_CHAT_MODEL})"
+$seedOk = ($LASTEXITCODE -eq 0)
+Pop-Location
+if ($seedOk) { Write-OK "Default model set to $ChatModel" }
+else { Write-Warn "Could not persist default model - pick it at the top of the chat instead." }
+
 Write-Step "Pulling models ($ChatModel for chat, $MemModel for memory)"
-Write-Host "    Downloads a few GB; press Ctrl+C to skip and pull them later from the Models tab." -ForegroundColor DarkGray
+# A prompt, not "press Ctrl+C to skip": Ctrl+C in PowerShell 5.1 terminates the
+# whole script, so the escape hatch the installer advertised was also the one
+# thing that stopped it finishing - no Ollama cleanup, no summary, no window
+# close. Answering "n" declines the download and the installer carries on.
+Write-Host "    These are several GB. You can skip and pull them later from the Models tab." -ForegroundColor DarkGray
+$pullAnswer = Read-Host "    Download them now? [Y/n]"
+if ($pullAnswer -match '^\s*(n|no)\s*$') {
+    Write-Warn "Model download skipped - get them from the Models tab when you are ready."
+} else {
 # No pipe: 'ollama pull' draws a progress bar with cursor control, and piping it
 # (to Out-Host or anything else) buffers the redraws - the download then shows no
 # output for minutes and reads as a hang. Let it own the console.
@@ -257,16 +277,7 @@ else { Write-Warn "$ChatModel pull skipped/failed - pull it from the Models tab
     ollama pull $MemModel
     if ($LASTEXITCODE -eq 0) { Write-OK "$MemModel ready (memory curator)" }
     else { Write-Warn "$MemModel pull skipped/failed - the memory service will fall back to the chat model." }
-
-# Pin it as the default chat model. Runs from the repo root so the synapse
-# package imports; only writes the 'model' setting in the shared DB.
-Write-Step "Setting $ChatModel as the default model"
-Push-Location $RepoRoot
-& $VenvPy -c "from synapse.memory.store import store; from synapse.nexus_config import DEFAULT_CHAT_MODEL; store.update_settings({'model': DEFAULT_CHAT_MODEL})"
-$seedOk = ($LASTEXITCODE -eq 0)
-Pop-Location
-if ($seedOk) { Write-OK "Default model set to $ChatModel" }
-else { Write-Warn "Could not persist default model - pick it at the top of the chat instead." }
+}
 
 # -- Make Ollama manual-start (NexusOS owns the lifecycle) ----------------------
 Write-Step "Setting Ollama to manual start"
@@ -315,7 +326,7 @@ Write-Host "  A process reads PATH once, when it starts. This shell started befo
 Write-Host "  the installer put management\ on PATH, so it will never see ncp no" -ForegroundColor DarkGray
 Write-Host "  matter what you run here. The next terminal you open will." -ForegroundColor DarkGray
 Write-Host ""
-Read-Host "  Press Enter to close this window (Ctrl+C works too)"
+Read-Host "  Press Enter to close this window"
 
 # Stop-Process on our own PID, not `exit`: `exit` only ends the window when the
 # host was started with -File. Run interactively - `& .\install-windows.ps1` from

tests/test_smoke.py

@@ -95,6 +95,12 @@ def test_ncp_is_registered_on_path_not_in_a_shell_profile():
     assert ps1.index("ollama pull") > ps1.index("Creating desktop shortcut"), \
         "model pull must come after the desktop shortcut"
 
+    # And it must not TELL anyone to press Ctrl+C: in PS 5.1 that kills the
+    # script, so the advertised way to skip the download was also the way to
+    # abort the install. Skipping is a prompt now. Comments stripped so the
+    # comment explaining this does not trip the check.
+    assert "Ctrl+C" not in code, "installer must not offer Ctrl+C as a skip"
+
 
 def test_no_ps1_shadows_the_ncp_path_shim():
     """PowerShell resolves ExternalScript (.ps1) ahead of Application (.cmd), so