BUILD PR: remove unused helper imports after shared extraction (advanced modules only).

Author: DavidQ

docs/dev/CODEX_COMMANDS.md

@@ -1,11 +1,13 @@
 MODEL: GPT-5.3-codex
 REASONING: high
 COMMAND:
-Execute docs/pr/BUILD_PR_SHARED_EXTRACTION_08_IS_PLAIN_OBJECT_ADVANCED_ONLY.md exactly.
-Edit only these files:
+Execute docs/pr/BUILD_PR_SHARED_EXTRACTION_09_CLEAN_UNUSED_HELPER_IMPORTS_ADVANCED_ONLY.md exactly.
+
+Edit ONLY:
 - src/advanced/promotion/createPromotionGate.js
 - src/advanced/state/createWorldGameStateSystem.js
-- src/shared/utils/objectUtils.js (only if minimum export change is needed)
-Fail fast if src/shared/utils/objectUtils.js does not already exist and export or contain isPlainObject.
+
 Do not expand scope.
-Package the delta output to <project folder>/tmp/BUILD_PR_SHARED_EXTRACTION_08_IS_PLAIN_OBJECT_ADVANCED_ONLY_delta.zip
+
+Package to:
+<project folder>/tmp/BUILD_PR_SHARED_EXTRACTION_09_CLEAN_UNUSED_HELPER_IMPORTS_ADVANCED_ONLY_delta.zip

docs/dev/COMMIT_COMMENT.txt

@@ -1 +1 @@
-BUILD PR: remove remaining advanced-local isPlainObject duplicates and use shared object utils.
+BUILD PR: remove unused helper imports after shared extraction (advanced modules only).

docs/dev/NEXT_COMMAND.txt

@@ -1 +1 @@
-Next: if clean, continue with the next executable BUILD. If blocked, capture the exact blocker and narrow further without changing PR purpose.
+Next: continue executable BUILD chain

docs/dev/reports/change_summary.txt

@@ -1 +1 @@
-Built the next executable shared-extraction step for isPlainObject, constrained to the two advanced modules only and guarded by a fail-fast check on the existing shared object helper.
+Cleanup pass for unused imports after extraction steps.

docs/dev/reports/file_tree.txt

@@ -1,11 +1 @@
-docs/
-  pr/
-    BUILD_PR_SHARED_EXTRACTION_08_IS_PLAIN_OBJECT_ADVANCED_ONLY.md
-  dev/
-    codex_commands.md
-    commit_comment.txt
-    next_command.txt
-    reports/
-      change_summary.txt
-      validation_checklist.txt
-      file_tree.txt
+docs only

docs/dev/reports/validation_checklist.txt

@@ -1,9 +1 @@
-SESSION VALIDATION GATE
-- Bundle type: BUILD
-- One PR purpose only: yes
-- Exact target files listed: yes
-- Fail-fast dependency gate explicit: yes
-- No guessing/new helper creation: yes
-- Repo-wide scan/refactor language avoided: yes
-- Scope minimized: yes
-- ZIP repo-structured and execution-ready: yes
+Unused imports removed only.

docs/pr/BUILD_PR_SHARED_EXTRACTION_09_CLEAN_UNUSED_HELPER_IMPORTS_ADVANCED_ONLY.md

@@ -0,0 +1,46 @@
+# BUILD_PR_SHARED_EXTRACTION_09_CLEAN_UNUSED_HELPER_IMPORTS_ADVANCED_ONLY
+
+## Purpose
+Remove any UNUSED helper imports introduced during prior extraction steps.
+
+## Single PR Purpose
+Cleanup ONLY unused imports in:
+
+- src/advanced/promotion/createPromotionGate.js
+- src/advanced/state/createWorldGameStateSystem.js
+
+## Exact Files Allowed
+Edit ONLY:
+1. src/advanced/promotion/createPromotionGate.js
+2. src/advanced/state/createWorldGameStateSystem.js
+
+## Exact Rules
+- Identify imports for:
+  - asFiniteNumber
+  - asPositiveInteger
+  - isPlainObject
+  - createPromotionStateSnapshot
+
+- If ANY of the above are imported but NOT used in the file:
+  - remove that import
+
+- If used:
+  - keep import unchanged
+
+## Hard Constraints
+- DO NOT modify logic
+- DO NOT reorder imports
+- DO NOT touch other imports
+- DO NOT scan repo
+- DO NOT modify shared files
+
+## Validation Checklist
+1. Only 2 files changed
+2. No unused imports remain for the listed helpers
+3. No used imports were removed
+4. No logic changed
+
+## Non-Goals
+- no formatting cleanup
+- no linting changes
+- no refactor

src/advanced/promotion/createPromotionGate.js

@@ -5,7 +5,7 @@ David Quesenberry
 createPromotionGate.js
 */
 
-import { asFiniteNumber, asPositiveInteger } from '../../shared/utils/numberUtils.js';
+import { asPositiveInteger } from '../../shared/utils/numberUtils.js';
 import { isPlainObject } from '../../shared/utils/objectUtils.js';
 import { createPromotionStateSnapshot } from '../shared/state/createPromotionStateSnapshot.js';
 

src/advanced/state/createWorldGameStateSystem.js

@@ -19,7 +19,7 @@ import {
   createTransitionRejectedEvent
 } from './events.js';
 import { createPromotionStateSnapshot } from '../../shared/state/createPromotionStateSnapshot.js';
-import { asFiniteNumber, asPositiveInteger } from '../../shared/utils/numberUtils.js';
+import { asPositiveInteger } from '../../shared/utils/numberUtils.js';
 import { isPlainObject } from '../../shared/utils/objectUtils.js';
 import {
   cloneDeep,