fix(web): 修復排版邊界與增量生命週期

src/typeset/lineedge.ts

@@ -61,13 +61,15 @@ function installLayout(
     if (!m) { m = new Map(); owners.set(owner, m); }
     const existing = m.get(key);
     if (existing) { existing.disconnect(); }
-    const ro = new ResizeObserver(() => run());
-    ro.observe(root);
+    // 字型 Promise／已排隊回調可能晚於 revert 或重裝；只允許目前安裝執行。
+    const runCurrent = (): void => { if (m!.get(key) === ro) { run(); } };
+    const ro = new ResizeObserver(runCurrent);
     m.set(key, ro);
+    ro.observe(root);
     const fonts = (root.ownerDocument as Document & { fonts?: { ready?: Promise<unknown> } }).fonts;
     if (fonts && fonts.ready && typeof fonts.ready.then === "function")
     {
-        fonts.ready.then(run, () => undefined);
+        fonts.ready.then(runCurrent, () => undefined);
     }
 }
 
@@ -331,7 +333,8 @@ function trimGaps(
     {
         const r = lastRect(g);
         const next = r ? edgeRect(g.nextSibling, "next", g, wrapSet) : null;
-        const atLineEnd = !r || !next || next.top > r.top + EPS;
+        // 同行小字／下標的 top 亦會較低；須整體落到下一行才算行末。
+        const atLineEnd = !r || !next || lowerLine(r, next);
         if (!atLineEnd) { ctx.setOwnedClass(g, TRIM, false); }
     }
 }