feat(tui): add vitest kill + memory-pressure auto-kill to Utilities

[k] kills all running vitest processes via pgrep -f. [v] toggles a
sampler-driven guard that SIGKILLs vitest when system memory exceeds
90%, throttled to once per 30s. Auto-kill defaults ON.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/cli/src/commands/dashboard-tui/app.tsx

@@ -589,11 +589,14 @@ function ExpandedLog({ entry, index, total }: { entry: LogEntry; index: number;
 
 // ── Utilities panel ───────────────────────────────────────────────────────────
 
-function UtilitiesPanel({ isFocused }: { isFocused: boolean }) {
-  const actions = [
+function UtilitiesPanel({ state, isFocused }: { state: DashboardState; isFocused: boolean }) {
+  const autoKill = state.autoKillVitestOnPressure;
+  const actions: Array<{ key: string; label: string }> = [
     { key: "r", label: "Refresh Stats" },
     { key: "c", label: "Clear Logs" },
     { key: "t", label: "Toggle Engine Pause" },
+    { key: "k", label: "Kill Vitest Processes" },
+    { key: "v", label: `Auto-Kill Vitest >90% Mem: ${autoKill ? "ON" : "OFF"}` },
     { key: "?", label: "Help" },
   ];
   return (
@@ -628,6 +631,8 @@ function HelpOverlay() {
     ["[←] / [p]", "Previous panel (Main)"],
     ["[r]", "Refresh stats (Utilities)"],
     ["[c]", "Clear logs (Utilities)"],
+    ["[k]", "Kill all vitest processes (Utilities)"],
+    ["[v]", "Toggle auto-kill vitest >90% mem (Utilities)"],
     ["[↑/↓/k/j]", "Navigate list / log entries"],
     ["[Home / G]", "First / last log entry (Logs)"],
     ["[Enter/Space]", "Expand log entry (Logs)"],
@@ -707,7 +712,7 @@ function StatusModeGrid({
           />
           <Box flexDirection="row" overflow="hidden">
             <Box flexDirection="column" flexGrow={1} overflow="hidden">
-              <UtilitiesPanel isFocused={focused === "utilities"} />
+              <UtilitiesPanel state={state} isFocused={focused === "utilities"} />
             </Box>
             <Box flexDirection="column" flexGrow={1} overflow="hidden">
               <SettingsPanel state={state} isFocused={focused === "settings"} />
@@ -736,7 +741,7 @@ function StatusModeSingle({
     switch (focused) {
       case "system": return <SystemPanel state={state} isFocused />;
       case "logs": return <LogsPanel state={state} isFocused availableRows={Math.max(4, (process.stdout.rows ?? 24) - 8)} />;
-      case "utilities": return <UtilitiesPanel isFocused />;
+      case "utilities": return <UtilitiesPanel state={state} isFocused />;
       case "stats": return <StatsPanel state={state} isFocused />;
       case "settings": return <SettingsPanel state={state} isFocused />;
     }
@@ -764,7 +769,7 @@ function StatusBar({ state, controller: _controller }: { state: DashboardState;
   if (activeSection === "logs") {
     hotkeys.push("↑↓ navigate", "w wrap", "f filter", "Enter expand");
   } else if (activeSection === "utilities") {
-    hotkeys.push("r refresh", "c clear logs", "t toggle pause");
+    hotkeys.push("r refresh", "c clear logs", "t toggle pause", "k kill vitest", "v auto-kill");
   } else {
     hotkeys.push("Tab cycle panel", "1-5 jump");
   }

packages/cli/src/commands/dashboard-tui/controller.ts

@@ -50,6 +50,12 @@ export class DashboardTUI {
   logsViewportStart = 0;
   loadingStatus = "Starting…";
   mode: "status" | "interactive" = "status";
+  // When true, sampleSystemStats() kills any running vitest processes if
+  // system memory usage crosses 90%. Toggled by [v] in the Utilities panel.
+  autoKillVitestOnPressure = true;
+  // Throttle so we don't spam kills while the sampler keeps firing during
+  // sustained pressure (sampler runs every 2s).
+  private lastAutoKillAt = 0;
   interactiveData: InteractiveData | null = null;
   interactiveView: InteractiveView = "board";
 
@@ -110,6 +116,7 @@ export class DashboardTUI {
       mode: this.mode,
       interactiveData: this.interactiveData,
       interactiveView: this.interactiveView,
+      autoKillVitestOnPressure: this.autoKillVitestOnPressure,
     };
     return this.cachedSnapshot;
   }
@@ -195,6 +202,68 @@ export class DashboardTUI {
       nodeVersion: process.version,
       platform: `${process.platform}/${process.arch}`,
     });
+
+    if (this.autoKillVitestOnPressure) {
+      const total = os.totalmem();
+      const free = os.freemem();
+      if (total > 0) {
+        const usedRatio = (total - free) / total;
+        // 30s minimum gap between auto-kills — vitest restart and OS reclaim
+        // both take a few seconds; firing every 2s would flap.
+        if (usedRatio > 0.9 && now - this.lastAutoKillAt > 30_000) {
+          this.lastAutoKillAt = now;
+          const result = this.killVitestProcesses();
+          if (result.killed > 0) {
+            this.warn(
+              `Auto-killed ${result.killed} vitest process${result.killed === 1 ? "" : "es"} (system memory at ${Math.round(usedRatio * 100)}%)`,
+              "memory-guard",
+            );
+          }
+        }
+      }
+    }
+  }
+
+  /**
+   * Find and SIGKILL any running vitest processes, excluding this dashboard
+   * itself. Returns a count of pids signalled (best-effort — a pid may be
+   * gone by the time we send the signal).
+   */
+  killVitestProcesses(): { killed: number; pids: number[] } {
+    const selfPid = process.pid;
+    let pids: number[] = [];
+    try {
+      // pgrep -f matches against the full command line. -a would include the
+      // command, but we only need pids. macOS and Linux both support -f.
+      const out = execSync("pgrep -f vitest", { encoding: "utf8", stdio: ["ignore", "pipe", "ignore"] });
+      pids = out
+        .split("\n")
+        .map((s) => Number.parseInt(s.trim(), 10))
+        .filter((n) => Number.isFinite(n) && n > 0 && n !== selfPid);
+    } catch {
+      // pgrep exits non-zero when no matches — treat as "nothing to kill".
+      return { killed: 0, pids: [] };
+    }
+
+    let killed = 0;
+    for (const pid of pids) {
+      try {
+        process.kill(pid, "SIGKILL");
+        killed += 1;
+      } catch {
+        // Process already exited or we lack permission — skip.
+      }
+    }
+    return { killed, pids };
+  }
+
+  toggleAutoKillVitest(): boolean {
+    this.autoKillVitestOnPressure = !this.autoKillVitestOnPressure;
+    if (!this.autoKillVitestOnPressure) {
+      this.lastAutoKillAt = 0;
+    }
+    this.notify();
+    return this.autoKillVitestOnPressure;
   }
 
   setSettings(settings: SettingsValues): void {
@@ -335,6 +404,26 @@ export class DashboardTUI {
           this.setSettings(newSettings);
         }
         break;
+      case "k": {
+        const result = this.killVitestProcesses();
+        if (result.killed === 0) {
+          this.log("No vitest processes found.", "kill-vitest");
+        } else {
+          this.warn(
+            `Killed ${result.killed} vitest process${result.killed === 1 ? "" : "es"}: ${result.pids.join(", ")}`,
+            "kill-vitest",
+          );
+        }
+        break;
+      }
+      case "v": {
+        const enabled = this.toggleAutoKillVitest();
+        this.log(
+          `Auto-kill vitest on memory pressure (>90%): ${enabled ? "ON" : "OFF"}`,
+          "memory-guard",
+        );
+        break;
+      }
     }
   }
 

packages/cli/src/commands/dashboard-tui/state.ts

@@ -279,6 +279,7 @@ export interface DashboardState {
   mode: AppMode;
   interactiveData: InteractiveData | null;
   interactiveView: InteractiveView;
+  autoKillVitestOnPressure: boolean;
 }
 
 export const SECTION_ORDER: SectionId[] = ["system", "logs", "utilities", "stats", "settings"];
@@ -302,5 +303,6 @@ export function createInitialState(): DashboardState {
     mode: "status",
     interactiveData: null,
     interactiveView: "board",
+    autoKillVitestOnPressure: true,
   };
 }