feat: colored installer output with status indicators and next steps

- Green ✓ for success, yellow ⚠ for warnings, red ✗ for errors
- Bold section headings (Installing, Post-install, PATH, Summary)
- Summary block with numbered next steps (source shell profile, mosaic init)
- Suppressed noisy sub-script output — only status lines shown
- Colors auto-disabled when not running in a terminal (piped output)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

install.ps1

@@ -9,10 +9,16 @@ $ErrorActionPreference = "Stop"
 $SourceDir = $PSScriptRoot
 $TargetDir = if ($env:MOSAIC_HOME) { $env:MOSAIC_HOME } else { Join-Path $env:USERPROFILE ".config\mosaic" }
 
+function Write-Ok   { param([string]$Msg) Write-Host "  ✓ " -ForegroundColor Green -NoNewline; Write-Host $Msg }
+function Write-Warn { param([string]$Msg) Write-Host "  ⚠ " -ForegroundColor Yellow -NoNewline; Write-Host $Msg }
+function Write-Fail { param([string]$Msg) Write-Host "  ✗ " -ForegroundColor Red -NoNewline; Write-Host $Msg }
+function Write-Step { param([string]$Msg) Write-Host ""; Write-Host $Msg -ForegroundColor White -BackgroundColor DarkGray }
+
+# ── Install framework ────────────────────────────────────────
+Write-Step " Installing Mosaic framework "
+
 if (-not (Test-Path $TargetDir)) { New-Item -ItemType Directory -Path $TargetDir -Force | Out-Null }
 
-# Sync files: remove old content, copy new
-Write-Host "[mosaic-install] Copying framework to $TargetDir..."
 Get-ChildItem $TargetDir -Exclude ".git" | Remove-Item -Recurse -Force
 Get-ChildItem $SourceDir -Exclude ".git" | ForEach-Object {
     $dest = Join-Path $TargetDir $_.Name
@@ -24,67 +30,89 @@ Get-ChildItem $SourceDir -Exclude ".git" | ForEach-Object {
     }
 }
 
-Write-Host "[mosaic-install] Installed framework to $TargetDir"
+Write-Ok "Framework installed to $TargetDir"
+
+# ── Post-install tasks ───────────────────────────────────────
+Write-Step " Post-install tasks "
 
-# Run post-install scripts (PowerShell versions)
 $binDir = Join-Path $TargetDir "bin"
 
-Write-Host "[mosaic-install] Linking runtime compatibility assets"
 try {
-    & "$binDir\mosaic-link-runtime-assets.ps1"
+    & "$binDir\mosaic-link-runtime-assets.ps1" *>$null
+    Write-Ok "Runtime assets linked"
 }
 catch {
-    Write-Host "[mosaic-install] WARNING: runtime asset linking failed (framework install still complete)" -ForegroundColor Yellow
+    Write-Warn "Runtime asset linking failed (non-fatal)"
 }
 
-Write-Host "[mosaic-install] Syncing universal skills"
 if ($env:MOSAIC_SKIP_SKILLS_SYNC -eq "1") {
-    Write-Host "[mosaic-install] Skipping skills sync (MOSAIC_SKIP_SKILLS_SYNC=1)"
+    Write-Ok "Skills sync skipped (MOSAIC_SKIP_SKILLS_SYNC=1)"
 }
 else {
     try {
-        & "$binDir\mosaic-sync-skills.ps1"
+        & "$binDir\mosaic-sync-skills.ps1" *>$null
+        Write-Ok "Skills synced"
     }
     catch {
-        Write-Host "[mosaic-install] WARNING: skills sync failed (framework install still complete)" -ForegroundColor Yellow
+        Write-Warn "Skills sync failed (non-fatal)"
     }
 }
 
-Write-Host "[mosaic-install] Migrating runtime-local skills to Mosaic junctions"
 try {
-    & "$binDir\mosaic-migrate-local-skills.ps1" -Apply
+    & "$binDir\mosaic-migrate-local-skills.ps1" -Apply *>$null
+    Write-Ok "Local skills migrated"
 }
 catch {
-    Write-Host "[mosaic-install] WARNING: local skill migration failed (framework install still complete)" -ForegroundColor Yellow
+    Write-Warn "Local skill migration failed (non-fatal)"
 }
 
-Write-Host "[mosaic-install] Running health audit"
 try {
-    & "$binDir\mosaic-doctor.ps1"
+    & "$binDir\mosaic-doctor.ps1" *>$null
+    Write-Ok "Health audit passed"
 }
 catch {
-    Write-Host "[mosaic-install] WARNING: doctor reported issues (run mosaic-doctor.ps1 -FailOnWarn)" -ForegroundColor Yellow
+    Write-Warn "Health audit reported issues — run 'mosaic doctor' for details"
 }
 
-# Ensure mosaic bin is in User PATH persistently
+# ── PATH configuration ───────────────────────────────────────
+Write-Step " PATH configuration "
+
 $mosaicBin = Join-Path $TargetDir "bin"
 $userPath = [Environment]::GetEnvironmentVariable("Path", "User")
+$pathChanged = $false
+
 if ($userPath -and $userPath.Split(";") -contains $mosaicBin) {
-    Write-Host "[mosaic-install] PATH: $mosaicBin already in User PATH ✓"
+    Write-Ok "Already in User PATH"
 }
 else {
     $newPath = if ($userPath) { "$mosaicBin;$userPath" } else { $mosaicBin }
     [Environment]::SetEnvironmentVariable("Path", $newPath, "User")
     $env:Path = "$mosaicBin;$env:Path"
-    Write-Host "[mosaic-install] PATH: Added $mosaicBin to User PATH ✓"
-    Write-Host "[mosaic-install] Open a new terminal for PATH changes to take effect."
+    Write-Ok "Added to User PATH"
+    $pathChanged = $true
 }
 
-Write-Host "[mosaic-install] Done."
+# ── Summary ──────────────────────────────────────────────────
+Write-Host ""
+Write-Host "  Mosaic installed successfully." -ForegroundColor Green
+Write-Host ""
+
+$nextSteps = @()
+
+if ($pathChanged) {
+    $nextSteps += "Open a new terminal (or log out and back in) to activate PATH."
+}
 
 $soulPath = Join-Path $TargetDir "SOUL.md"
 if (-not (Test-Path $soulPath)) {
-    Write-Host ""
-    Write-Host "[mosaic-install] Set up your agent identity by running: mosaic init"
-    Write-Host "[mosaic-install] This generates SOUL.md - the universal behavioral contract for all agent sessions."
+    $nextSteps += "Run 'mosaic init' to set up your agent identity (SOUL.md)."
+}
+
+if ($nextSteps.Count -gt 0) {
+    Write-Host "  Next steps:" -ForegroundColor White
+    for ($i = 0; $i -lt $nextSteps.Count; $i++) {
+        Write-Host "  $($i + 1). " -NoNewline
+        Write-Host $nextSteps[$i] -ForegroundColor Cyan
+    }
+    Write-Host ""
 }