refactor(utils/clean + providers/registry + plugins/auth): selective (ADR-025 L2)

Three files with 3 stars each -> selective.

utils/clean.nu:
  utils/logging.nu   [is-debug-enabled]
  utils/interface.nu [_ansi _print]
  config/accessor    DROPPED (dead)

providers/registry.nu:
  config/accessor/core.nu [config-get]
  utils/logging.nu        [log-debug]
  providers/interface.nu  DROPPED (dead)

plugins/auth.nu:
  config/accessor/core.nu [config-get]
  auth_impl.nu (re-export) [23 symbols]  — converted to explicit list
  utils/path-utils.nu  DROPPED (dead)

Validation: all 3 nu --ide-check 50 -> 0 errors.

Refs: ADR-025

nulib/lib_provisioning/plugins/auth.nu

@@ -2,9 +2,19 @@
 # Purpose: Provides JWT authentication, MFA enrollment/verification, auth status checking, and permission validation.
 # Dependencies: std log, path-utils, auth_impl
 
-use ../config/accessor.nu *
-use ../utils/path-utils.nu *
-export use auth_impl.nu *
+# Selective imports + re-exports (ADR-025 Phase 3 Layer 2).
+# utils/path-utils star-import was dead — dropped.
+use lib_provisioning/config/accessor/core.nu [config-get]
+export use auth_impl.nu [
+    check-auth-for-destructive check-auth-for-production check-operation-auth
+    get-api-key-interactive get-auth-metadata get-authenticated-user
+    get-provider-credentials-interactive get-secret-config-interactive
+    is-authenticated is-check-mode is-destructive-operation is-mfa-verified
+    log-authenticated-operation login-interactive mfa-enroll-interactive
+    print-auth-status require-auth require-mfa run-typedialog-auth-form
+    should-enforce-auth-from-metadata should-require-auth
+    should-require-mfa-destructive should-require-mfa-prod
+]
 
 # Check if Auth plugin is available (registered with Nushell)
 def is-plugin-available [] {

nulib/lib_provisioning/providers/registry.nu

@@ -1,9 +1,10 @@
 # Provider Registry System
 # Dynamic provider discovery, registration, and management
 
-use ../config/accessor.nu *
-use ../utils/logging.nu *
-use interface.nu *
+# Selective imports (ADR-025 Phase 3 Layer 2).
+# providers/interface.nu star-import was dead — dropped.
+use lib_provisioning/config/accessor/core.nu [config-get]
+use lib_provisioning/utils/logging.nu [log-debug]
 
 # Provider registry cache file path
 def get-provider-cache-file [] {

nulib/lib_provisioning/utils/clean.nu

@@ -1,6 +1,7 @@
-use ../config/accessor.nu *
-use ./logging.nu *
-use ./interface.nu *
+# Selective imports (ADR-025 Phase 3 Layer 2).
+# config/accessor star-import was dead — dropped.
+use lib_provisioning/utils/logging.nu [is-debug-enabled]
+use lib_provisioning/utils/interface.nu [_ansi _print]
 
 export def cleanup  [
   wk_path: string