refactor(setup): selective imports in wizard/system/platform (ADR-025 L2)

Three setup/ files converted from star-imports to selective imports with
absolute paths. All three follow the same pattern (4 stars each -> selective),
bundled in one commit since they share the same dependency surface.

setup/wizard.nu:
  setup/mod.nu       [11 symbols — detection/print helpers]
  setup/detection.nu [4 symbols — deployment capabilities + report]
  utils/path-utils.nu [get-typedialog-form-path]
  setup/validation.nu  DROPPED (0 used symbols — dead import)

setup/system.nu:
  setup/mod.nu    [17 symbols — ensure-config-dirs + print + sys info + save]
  setup/wizard.nu [3 symbols — run-*]
  utils/nickel_processor.nu [ncl-eval-soft]  (kept, already selective)
  setup/detection.nu   DROPPED (0 used)
  setup/validation.nu  DROPPED (0 used)

setup/platform.nu:
  setup/mod.nu        [11 symbols — print + sys info + save/load TOML]
  setup/detection.nu  [5 symbols — has-docker/kubectl/...]
  platform/bootstrap.nu [bootstrap-platform]
  setup/validation.nu   DROPPED (0 used)

Validation (all 3): nu --ide-check 50 -> 0 errors, matches baseline.

Refs: ADR-025, .coder/benchmarks/phase2-transitivity.md Layer 2

nulib/lib_provisioning/setup/platform.nu

@@ -2,10 +2,17 @@
 # Manages deployment and initialization of platform services (Orchestrator, Control Center, KMS)
 # Follows Nushell guidelines: explicit types, single purpose, no try-catch
 
-use ./mod.nu *
+# Selective imports (ADR-025 Phase 3 Layer 2).
-use ./detection.nu *
+# setup/validation.nu star-import was dead — dropped.
-use ./validation.nu *
+use lib_provisioning/setup/mod.nu [
-use ../platform/bootstrap.nu *
+    get-config-base-path get-cpu-count get-system-memory-gb
+    get-timestamp-iso8601 load-config-toml print-setup-error print-setup-header
+    print-setup-info print-setup-success print-setup-warning save-config-toml
+]
+use lib_provisioning/setup/detection.nu [
+    has-docker has-docker-compose has-kubectl has-ssh has-systemd
+]
+use lib_provisioning/platform/bootstrap.nu [bootstrap-platform]
 
 # ============================================================================
 # DEPLOYMENT MODE VALIDATION

nulib/lib_provisioning/setup/system.nu

@@ -2,11 +2,19 @@
 # Orchestrates complete provisioning system setup and initialization
 # Follows Nushell guidelines: explicit types, single purpose, no try-catch
 
-use ./mod.nu *
+# Selective imports (ADR-025 Phase 3 Layer 2).
-use ./detection.nu *
+# setup/detection.nu and setup/validation.nu star-imports were dead — dropped.
-use ./validation.nu *
+use lib_provisioning/setup/mod.nu [
-use ./wizard.nu *
+    detect-architecture detect-os ensure-config-dirs get-config-base-path
-use ../utils/nickel_processor.nu [ncl-eval-soft]
+    get-cpu-count get-current-user get-system-disk-gb get-system-hostname
+    get-system-memory-gb get-timestamp-iso8601 print-setup-error
+    print-setup-header print-setup-info print-setup-success print-setup-warning
+    save-config-toml save-config-yaml
+]
+use lib_provisioning/setup/wizard.nu [
+    run-minimal-setup run-setup-with-defaults run-setup-wizard
+]
+use lib_provisioning/utils/nickel_processor.nu [ncl-eval-soft]
 
 # ============================================================================
 # SYSTEM CONFIGURATION CREATION

nulib/lib_provisioning/setup/wizard.nu

@@ -8,10 +8,18 @@
 # version = "3.0.0"
 # requires = ["nushell:0.109.0"]
 
-use ./mod.nu *
+# Selective imports (ADR-025 Phase 3 Layer 2).
-use ./detection.nu *
+# setup/validation.nu star-import was dead (no used symbols) — dropped.
-use ./validation.nu *
+use lib_provisioning/setup/mod.nu [
-use ../utils/path-utils.nu *
+    detect-architecture detect-os get-config-base-path get-cpu-count
+    get-current-user get-system-memory-gb print-setup-error print-setup-header
+    print-setup-info print-setup-success print-setup-warning
+]
+use lib_provisioning/setup/detection.nu [
+    get-deployment-capabilities get-existing-config-summary
+    print-detection-report recommend-deployment-mode
+]
+use lib_provisioning/utils/path-utils.nu [get-typedialog-form-path]
 
 # ============================================================================
 # INPUT HELPERS