fix: address 5 edge cases from review-work findings

- C3: include command args in auto-slash-command dedup key
- H2: track completed task summaries for ALL COMPLETE message
- H9: increment tmux close retry count on re-mark
- H8: detect stale MCP connections after disconnect+reconnect race
- H8: guard disconnectedSessions growth for non-MCP sessions
- C1: await tmux cleanup in plugin dispose lifecycle

src/features/skill-mcp-manager/connection.ts

@@ -29,9 +29,16 @@ export async function getOrCreateClient(params: {
   }
 
   const expandedConfig = expandEnvVarsInObject(config)
-  const connectionPromise = (async () => {
+  let currentConnectionPromise!: Promise<Client>
+  currentConnectionPromise = (async () => {
     const client = await createClient({ state, clientKey, info, config: expandedConfig })
 
+    const isStale = state.pendingConnections.has(clientKey) && state.pendingConnections.get(clientKey) !== currentConnectionPromise
+    if (isStale) {
+      try { await client.close() } catch {}
+      throw new Error(`Connection for "${info.sessionID}" was superseded by a newer connection attempt.`)
+    }
+
     if (state.disconnectedSessions.has(info.sessionID)) {
       await forceReconnect(state, clientKey)
       throw new Error(`Session "${info.sessionID}" disconnected during MCP connection setup.`)
@@ -40,13 +47,13 @@ export async function getOrCreateClient(params: {
     return client
   })()
 
-  state.pendingConnections.set(clientKey, connectionPromise)
+  state.pendingConnections.set(clientKey, currentConnectionPromise)
 
   try {
-    const client = await connectionPromise
+    const client = await currentConnectionPromise
     return client
   } finally {
-    if (state.pendingConnections.get(clientKey) === connectionPromise) {
+    if (state.pendingConnections.get(clientKey) === currentConnectionPromise) {
       state.pendingConnections.delete(clientKey)
     }
   }