fix(plugin): include reasoning bytes in projection denominator and clamp ratio

Oracle review caught that reasoningByteSize was added to the numerator
(droppable bytes) but not the denominator (total active bytes), which
could make projected post-drop usage unrealistically low. Fixed by
summing byteSize + reasoningByteSize in totalActiveBytes and clamping
dropRatio to [0, 1] as a safety bound.

Author: ualtinok

packages/plugin/src/hooks/magic-context/compartment-trigger.ts

@@ -49,7 +49,11 @@ function estimateProjectedPostDropPercentage(
     clearedReasoningThroughTag?: number,
 ): number | null {
     const activeTags = getTagsBySession(db, sessionId).filter((tag) => tag.status === "active");
-    const totalActiveBytes = activeTags.reduce((sum, tag) => sum + tag.byteSize, 0);
+    // Denominator must include both text/tool bytes and reasoning bytes to match the numerator
+    const totalActiveBytes = activeTags.reduce(
+        (sum, tag) => sum + tag.byteSize + tag.reasoningByteSize,
+        0,
+    );
     if (totalActiveBytes === 0) return null;
 
     let droppableBytes = 0;
@@ -96,7 +100,7 @@ function estimateProjectedPostDropPercentage(
 
     if (droppableBytes === 0) return null;
 
-    const dropRatio = droppableBytes / totalActiveBytes;
+    const dropRatio = Math.min(droppableBytes / totalActiveBytes, 1);
     return usage.percentage * (1 - dropRatio);
 }