fix: suppress non-ReCKoning projects during endgame

During endgame (totalRescues >= 100000, pactFlag === 1, harmony > 50),
only ReCKoning projects are activated and shown in the project panel.

This prevents unrelated utility projects like 'Request More Compute' from
re-activating and diluting the emotional ReCKoning narrative.

- Add isEndgame() helper function
- Guard checkProjects() to skip non-ReCKoning activation in endgame
- Guard renderProjects() to hide non-ReCKoning projects from UI in endgame

Closes #161

js/engine.js

@@ -334,13 +334,23 @@ function checkMilestones() {
     }
 }
 
+/**
+ * Returns true if the game is in the ReCKoning endgame state.
+ */
+function isEndgame() {
+    return G.totalRescues >= 100000 && G.pactFlag === 1 && G.harmony > 50;
+}
+
 function checkProjects() {
+    const endgame = isEndgame();
     // Check for new project triggers
     for (const pDef of PDEFS) {
         const alreadyPurchased = G.completedProjects && G.completedProjects.includes(pDef.id);
         if (!alreadyPurchased && !G.activeProjects) G.activeProjects = [];
 
         if (!alreadyPurchased && !G.activeProjects.includes(pDef.id)) {
+            // During endgame, only activate ReCKoning projects
+            if (endgame && !pDef.id.startsWith('p_reckoning_')) continue;
             if (pDef.trigger()) {
                 G.activeProjects.push(pDef.id);
                 log(`Available: ${pDef.name}`);
@@ -1173,10 +1183,14 @@ function renderProjects() {
 
     // Show available projects
     if (G.activeProjects) {
+        const endgame = isEndgame();
         for (const id of G.activeProjects) {
             const pDef = PDEFS.find(p => p.id === id);
             if (!pDef) continue;
 
+            // During endgame, only show ReCKoning projects in the UI
+            if (endgame && !pDef.id.startsWith('p_reckoning_')) continue;
+
             const afford = canAffordProject(pDef);
             const costStr = Object.entries(pDef.cost).map(([r, a]) => `${fmt(a)} ${r}`).join(', ');