fix: guard the JEI gas-giant-refresh call so it loads without JEI (Advanced-Rocketry#76)

PacketDimInfo.executeClient called ARPlugin.requestGasGiantRefresh()
unconditionally. ARPlugin implements mezz.jei.api.IModPlugin, so touching
it loads JEI classes and NoClassDefFoundErrors when JEI isn't installed —
re-introducing issue Advanced-Rocketry#76 via the dimension-sync path (the startup path
kaduvill already guarded in ClientProxy). Wrap the call in
Loader.isModLoaded("jei") and drop the top-level ARPlugin import.

Also files TASK-46: CompatibilityMgr is vestigial (all consumers gone or
commented out); left in place pending a revive-vs-remove decision.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: StannisMod

.agent/tasks/README.md

@@ -375,6 +375,7 @@ entry is an actionable TASK with a defined plan + acceptance.
 | [TASK-15](TASK-15-visual-regression.md) | Visual regression infrastructure for Minecraft client | ❌ Not planned | Closed 2026-05-29 — speculative infra with no live trigger and high build cost. Original 4 promotion triggers retained in task file; re-open via a new TASK if any fires. |
 | [TASK-16](TASK-16-test-stability-flake-watch.md) | Test-stability flake watch — investigation deliverable. Three flake shapes root-caused; shape #3 mitigated in TASK-26 via kit retry; #1+#2 split into TASK-27; #4 (worldgen sampling) confirmed across 3 sightings, promoted to TASK-28 F7. | 🟡 Investigation complete | Investigation done 2026-05-23. |
 | [TASK-45](TASK-45-oregen-clumpsize-clamp-disables-impossible.md) | `<oreGen>` `clumpSize`/`chancePerChunk` clamp to a floor of 1 (and empty `<oreGen>` falls through to the global pressure/temp default), so "disable this ore" is inexpressible per planet — likely the real cause behind #73's "zeroing veins still spawns ore". Analysis only; fix-vs-document undecided. | 🟡 Backlog — not started | Found 2026-06-01 alongside the #73 round-trip test. |
+| [TASK-46](TASK-46-compatibilitymgr-vestigial.md) | `CompatibilityMgr` is vestigial — `compat` instance never read, mod-presence flags written-but-not-read / set-by-uncalled-method, `reloadRecipes()` commented out. Kept on purpose (may regain meaning); decide revive vs remove. | 🟡 Backlog — not started | Found 2026-06-01 during the #76 JEI-ref audit. |
 
 ## Conscious non-goals
 

.agent/tasks/TASK-46-compatibilitymgr-vestigial.md

@@ -0,0 +1,54 @@
+# TASK-46: `CompatibilityMgr` is currently vestigial — decide revive vs remove
+
+## Ticket
+
+- Source: discovered 2026-06-01 while auditing `integration.jei` references
+  for the issue #76 JEI NoClassDefFoundError guard.
+- Status: 🟡 **Backlog — not started.** Deliberately left in place; the
+  maintainer may want to give it meaning again rather than delete it.
+- Created: 2026-06-01.
+
+## Context
+
+`integration/CompatibilityMgr.java` holds three static booleans plus a
+recipe-reload hook, but every live consumer is gone or commented out:
+
+- `AdvancedRocketry.compat = new CompatibilityMgr()` (AdvancedRocketry.java:173)
+  — instance created, **never read** anywhere.
+- `isSpongeInstalled` — written at `AdvancedRocketry.java:1145`, its only
+  read is commented out (`WorldProviderPlanet.java:232`). Written, never read.
+- `gregtechLoaded` / `thermalExpansionLoaded` — set only inside
+  `getLoadedMods()`, which has **no callers**. Never set, never read.
+- `getLoadedMods()` — uncalled.
+- `reloadRecipes()` — entirely commented out (also the only reference to
+  `integration.jei.ARPlugin` left in the file — a dead import).
+
+So the class does nothing observable today. It was historically the
+central "which integration mods are present" flag-holder + a JEI
+recipe-reload hook.
+
+## Why keep it for now
+
+Maintainer call (2026-06-01): not certain it should be removed — the
+mod-presence flags + a recipe-reload entry point may be given meaning
+again (e.g. real GregTech / ThermalExpansion / Sponge branches, or a
+working `/ar reloadrecipes`). Deleting now would just have to be
+re-created later.
+
+## Options (decide later)
+
+1. **Revive** — wire `getLoadedMods()` into mod init, uncomment the
+   reads that need the flags, and restore `reloadRecipes()` behind a
+   `Loader.isModLoaded("jei")` guard (so it can't re-introduce the #76
+   class-load crash). Then add coverage for the branches that read it.
+2. **Remove** — delete `CompatibilityMgr`, the unused `compat` field,
+   the dead `import ...jei.ARPlugin`, and the orphaned `isSpongeInstalled`
+   write. Smallest footprint; loses the scaffolding.
+3. **Leave as-is** — keep as a documented placeholder (current state).
+
+## Dependencies
+
+- Independent. Does NOT block the #76 guard (already shipped in
+  `PacketDimInfo`) or any other work.
+- If revived, the recipe-reload path MUST stay behind a JEI-loaded guard
+  — see the #76 fix rationale (touching `ARPlugin` loads JEI classes).

src/main/java/zmaster587/advancedRocketry/network/PacketDimInfo.java

@@ -9,7 +9,6 @@
 import zmaster587.advancedRocketry.AdvancedRocketry;
 import zmaster587.advancedRocketry.dimension.DimensionManager;
 import zmaster587.advancedRocketry.dimension.DimensionProperties;
-import zmaster587.advancedRocketry.integration.jei.ARPlugin;
 import zmaster587.advancedRocketry.util.SpawnListEntryNBT;
 import zmaster587.libVulpes.network.BasePacket;
 
@@ -146,7 +145,12 @@ public void executeClient(EntityPlayer thePlayer) {
                 DimensionManager.getInstance().registerDimNoUpdate(dimProperties, true);
             }
         }
-        ARPlugin.requestGasGiantRefresh();
+        // Guard the JEI integration: touching ARPlugin (implements mezz.jei.api
+        // IModPlugin) loads JEI classes, which NoClassDefFoundErrors when JEI
+        // isn't installed. See issue #76.
+        if (net.minecraftforge.fml.common.Loader.isModLoaded("jei")) {
+            zmaster587.advancedRocketry.integration.jei.ARPlugin.requestGasGiantRefresh();
+        }
     }
 
     @Override