Document required Unreal plugins

AGRARIAN_DEVELOPMENT_ROADMAP.md

@@ -176,7 +176,7 @@ Remaining version 0.01 cleanup before moving deeper into new gameplay:
 - [x] Implement Linastorage incremental project backup job.
 - [x] Implement quiesced VM backup job for Windows-Builder and Ubuntu-Codex.
 - [x] Create repeatable dedicated server build instructions.
-- [~] Finish required plugin documentation.
+- [x] Finish required plugin documentation.
 - [ ] Confirm the project opens cleanly from a fresh checkout, not just the current working share.
 - [ ] Organize `Content/Agrarian/` folders and move starter/prototype assets into clearly named locations.
 - [ ] Launch near-term MVP map-tile serving cloud VM.
@@ -214,7 +214,7 @@ Goal: Prepare the project so all future development is controlled, recoverable,
 - [x] Create repeatable local build instructions.
 - [x] Create repeatable packaged build instructions.
 - [x] Create repeatable dedicated server build instructions.
-- [~] Document required plugins.
+- [x] Document required plugins.
 - [x] Disable unneeded plugins.
 - [x] Confirm project compiles from a clean checkout.
 - [ ] Confirm project opens from a clean checkout.
@@ -1418,7 +1418,7 @@ Earliest incomplete foundation items:
 - [x] Implement Linastorage incremental project backup job.
 - [x] Implement quiesced VM backup job for Windows-Builder and Ubuntu-Codex.
 - [x] Create repeatable dedicated server build instructions.
-- [~] Finish required plugin documentation.
+- [x] Finish required plugin documentation.
 - [ ] Confirm project opens cleanly from a fresh checkout.
 - [ ] Create the core design document.
 - [ ] Create the technical design document.
@@ -1434,4 +1434,4 @@ Earliest incomplete foundation items:
 
 Immediate next item:
 
-- [~] Finish required plugin documentation.
+- [ ] Confirm project opens cleanly from a fresh checkout.