Clear sidebar notification when user submits prompt (#821)

* Clear sidebar notification when user submits prompt in Claude Code

Add UserPromptSubmit hook to the Claude Code wrapper that calls
`cmux claude-hook prompt-submit`. This clears the workspace notification
and sets status back to "Running" when the user addresses Claude's question,
so the "waiting for input" preview in the sidebar goes away.

Also adds --tab support to clear_notifications socket command and
--workspace support to the clear-notifications CLI command for
per-workspace notification clearing.

Closes https://github.com/manaflow-ai/cmux/issues/799

* Address review feedback: stricter error handling

- clear-notifications CLI: error on explicit --workspace failure instead of
  falling back to global clear. Env var still gracefully degrades.
- prompt-submit hook: propagate sendV1Command errors instead of swallowing
  with try?.
- clear_notifications socket: validate --tab flag is present before resolving,
  reject malformed args instead of falling back to selected tab.

* Gate env workspace fallback on windowId == nil in clear-notifications

Matches the pattern used by other CLI commands to avoid using
CMUX_WORKSPACE_ID from the caller shell when --window targets
a different window.

CLI/cmux.swift

@@ -1305,7 +1305,16 @@ struct CMUXCLI {
             }
 
         case "clear-notifications":
-            let response = try sendV1Command("clear_notifications", client: client)
+            var socketCmd = "clear_notifications"
+            if let wsFlag = optionValue(commandArgs, name: "--workspace") {
+                let wsId = try resolveWorkspaceId(wsFlag, client: client)
+                socketCmd += " --tab=\(wsId)"
+            } else if windowId == nil,
+                      let envWs = ProcessInfo.processInfo.environment["CMUX_WORKSPACE_ID"],
+                      let wsId = try? resolveWorkspaceId(envWs, client: client) {
+                socketCmd += " --tab=\(wsId)"
+            }
+            let response = try sendV1Command(socketCmd, client: client)
             print(response)
 
         case "claude-hook":
@@ -4441,7 +4450,7 @@ struct CMUXCLI {
             """
         case "claude-hook":
             return """
-            Usage: cmux claude-hook <session-start|active|stop|idle|notification|notify> [flags]
+            Usage: cmux claude-hook <session-start|active|stop|idle|notification|notify|prompt-submit> [flags]
 
             Hook for Claude Code integration. Reads JSON from stdin.
 
@@ -4452,6 +4461,7 @@ struct CMUXCLI {
               idle            Alias for stop
               notification    Forward a Claude notification
               notify          Alias for notification
+              prompt-submit   Clear notification and set Running on user prompt
 
             Flags:
               --workspace <id|ref>   Target workspace (default: $CMUX_WORKSPACE_ID)
@@ -5700,6 +5710,24 @@ struct CMUXCLI {
                 print("OK")
             }
 
+        case "prompt-submit":
+            telemetry.breadcrumb("claude-hook.prompt-submit")
+            var workspaceId = fallbackWorkspaceId
+            if let sessionId = parsedInput.sessionId,
+               let mapped = try? sessionStore.lookup(sessionId: sessionId),
+               let mappedWorkspace = try? resolveWorkspaceIdForClaudeHook(mapped.workspaceId, client: client) {
+                workspaceId = mappedWorkspace
+            }
+            _ = try sendV1Command("clear_notifications --tab=\(workspaceId)", client: client)
+            try setClaudeStatus(
+                client: client,
+                workspaceId: workspaceId,
+                value: "Running",
+                icon: "bolt.fill",
+                color: "#4C8DFF"
+            )
+            print("OK")
+
         case "notification", "notify":
             telemetry.breadcrumb("claude-hook.notification")
             let summary = summarizeClaudeHookNotification(rawInput: rawInput)

Resources/bin/claude

@@ -50,7 +50,7 @@ done
 
 # Build hooks settings JSON.
 # Claude Code merges --settings additively with the user's own settings.json.
-HOOKS_JSON='{"hooks":{"SessionStart":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook session-start","timeout":10}]}],"Stop":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook stop","timeout":10}]}],"Notification":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook notification","timeout":10}]}]}}'
+HOOKS_JSON='{"hooks":{"SessionStart":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook session-start","timeout":10}]}],"Stop":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook stop","timeout":10}]}],"Notification":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook notification","timeout":10}]}],"UserPromptSubmit":[{"matcher":"","hooks":[{"type":"command","command":"cmux claude-hook prompt-submit","timeout":10}]}]}}'
 
 if [[ "$SKIP_SESSION_ID" == true ]]; then
     exec "$REAL_CLAUDE" --settings "$HOOKS_JSON" "$@"

Sources/TerminalController.swift

@@ -878,7 +878,7 @@ class TerminalController {
             return listNotifications()
 
         case "clear_notifications":
-            return clearNotifications()
+            return clearNotifications(args)
 
         case "set_app_focus":
             return setAppFocusOverride(args)
@@ -8790,7 +8790,7 @@ class TerminalController {
           notify_surface <id|idx> <payload>  - Notify a specific surface
           notify_target <workspace_id> <surface_id> <payload> - Notify by workspace+surface
           list_notifications              - List all notifications
-          clear_notifications             - Clear all notifications
+          clear_notifications [--tab=X]    - Clear notifications (all or per-tab)
           set_app_focus <active|inactive|clear> - Override app focus state
           simulate_app_active             - Trigger app active handler
           set_status <key> <value> [--icon=X] [--color=#hex] [--url=X] [--priority=N] [--format=plain|markdown] [--tab=X] - Set a status entry
@@ -10124,9 +10124,30 @@ class TerminalController {
         return result.isEmpty ? "No notifications" : result
     }
 
-    private func clearNotifications() -> String {
+    private func clearNotifications(_ args: String) -> String {
+        let trimmed = args.trimmingCharacters(in: .whitespacesAndNewlines)
+        if trimmed.isEmpty {
+            DispatchQueue.main.sync {
+                TerminalNotificationStore.shared.clearAll()
+            }
+            return "OK"
+        }
+        let parsed = parseOptions(trimmed)
+        guard let tabOption = parsed.options["tab"],
+              !tabOption.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty else {
+            return "ERROR: Usage: clear_notifications [--tab=X]"
+        }
+        var tabId: UUID?
         DispatchQueue.main.sync {
-            TerminalNotificationStore.shared.clearAll()
+            if let tab = resolveTabForReport(trimmed) {
+                tabId = tab.id
+            }
+        }
+        guard let tabId else {
+            return "ERROR: Tab not found"
+        }
+        DispatchQueue.main.sync {
+            TerminalNotificationStore.shared.clearNotifications(forTabId: tabId)
         }
         return "OK"
     }