Add size() cardinality helper across modules (eighth pass).

Standardize a size() method after isEmpty() on every module with clearAll(), delegating to domain counts or snapshot fields so callers can query occupancy without parsing snapshots.

Co-authored-by: Cursor <[email protected]>

pear-platform/hyper-bare-headless-ui/index.js

@@ -129,6 +129,11 @@ class HyperBareHeadlessUi extends EventEmitter {
     return !s.pipeOpen && !s.ui
   }
 
+  size () {
+    const s = this.snapshot()
+    return (s.pipeOpen ? 1 : 0) + (s.ui ? 1 : 0)
+  }
+
   sendToUiBatch (messages) {
     if (!Array.isArray(messages)) throw new Error('messages array required')
     return messages.map((m) => this.sendToUi(m.channel, m.payload))