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/plugin-dispose.test.ts

@@ -16,6 +16,7 @@ describe("createPluginDispose", () => {
     const dispose = createPluginDispose({
       backgroundManager,
       skillMcpManager,
+      tmuxSessionManager: { cleanup: async (): Promise<void> => {} },
       disposeHooks: (): void => {},
     })
 
@@ -38,6 +39,7 @@ describe("createPluginDispose", () => {
     const dispose = createPluginDispose({
       backgroundManager,
       skillMcpManager,
+      tmuxSessionManager: { cleanup: async (): Promise<void> => {} },
       disposeHooks: (): void => {},
     })
 
@@ -69,6 +71,7 @@ describe("createPluginDispose", () => {
       skillMcpManager: {
         disconnectAll: async (): Promise<void> => {},
       },
+      tmuxSessionManager: { cleanup: async (): Promise<void> => {} },
       disposeHooks: (): void => {
         disposeCreatedHooks({
           runtimeFallback,
@@ -104,6 +107,7 @@ describe("createPluginDispose", () => {
     const dispose = createPluginDispose({
       backgroundManager,
       skillMcpManager,
+      tmuxSessionManager: { cleanup: async (): Promise<void> => {} },
       disposeHooks: disposeHooks.run,
     })