fix: detect idle state with inline suggestions and esc-to-interrupt signal

Claude Code shows inline suggestions after the prompt when idle (e.g.
"❯ check CI status on the PR"). Also strip separator lines (─) from
terminal output before detection. Use status bar "esc to interrupt"
presence as the authoritative active-vs-idle signal.

- Strip separator lines and empty lines alongside status bar lines
- Check raw output for "esc to interrupt" before stripping
- Treat ❯ + text as idle when status bar lacks esc to interrupt
- 4 new tests covering suggestion detection edge cases

packages/plugins/agent-claude-code/src/index.test.ts

@@ -423,6 +423,39 @@ describe("detectActivity", () => {
       agent.detectActivity("⏵⏵ bypass permissions on (shift+tab to cycle)\n"),
     ).toBe("idle");
   });
+
+  it("returns idle for prompt with separator and status bar (no esc to interrupt)", () => {
+    // Full TUI frame: prompt + separator + status bar, idle state
+    expect(
+      agent.detectActivity("❯ \n────────────────────────────────────────────────────────────────────────────────\n  ⏵⏵ bypass permissions on (shift+tab to cycle)"),
+    ).toBe("idle");
+  });
+
+  it("returns idle for prompt with inline suggestion (no esc to interrupt)", () => {
+    // Claude Code shows suggestions like "❯ check CI status" when idle
+    expect(
+      agent.detectActivity("❯ check CI status on the PR\n────────────────────────────────────────────────────────────────────────────────\n  ⏵⏵ bypass permissions on (shift+tab to cycle)"),
+    ).toBe("idle");
+  });
+
+  it("returns active for prompt with input being processed (esc to interrupt)", () => {
+    // When Claude Code is actively processing, status bar has "esc to interrupt"
+    expect(
+      agent.detectActivity("❯ fix the bug\n────────────────────────────────────────────────────────────────────────────────\n  ⏵⏵ bypass permissions on (shift+tab to cycle) · esc to interrupt"),
+    ).toBe("active");
+  });
+
+  it("returns idle for real finished session output with suggestion", () => {
+    const realOutput = [
+      "  - 18 new tests (12 for the command, 6 for plugin resolution) — all passing",
+      "✻ Churned for 10m 56s",
+      "────────────────────────────────────────────────────────────────────────────────",
+      "❯ check CI status on the PR",
+      "────────────────────────────────────────────────────────────────────────────────",
+      "  ⏵⏵ bypass permissions on (shift+tab to cycle)",
+    ].join("\n");
+    expect(agent.detectActivity(realOutput)).toBe("idle");
+  });
 });
 
 // =========================================================================

packages/plugins/agent-claude-code/src/index.ts

@@ -472,6 +472,13 @@ function classifyTerminalOutput(terminalOutput: string): ActivityState {
 
   const lines = terminalOutput.trim().split("\n");
 
+  // Claude Code's status bar is the most reliable activity signal:
+  // - Active:  "⏵⏵ bypass permissions on ... · esc to interrupt"
+  // - Idle:    "⏵⏵ bypass permissions on ..." (no esc to interrupt)
+  // Check BEFORE stripping decorative lines.
+  const rawTail = lines.slice(-3).join("\n");
+  const hasEscToInterrupt = /esc to interrupt/i.test(rawTail);
+
   // Strip trailing decorative lines from Claude Code's TUI. From bottom up,
   // remove: status bar lines (contain ⏵), separator lines (all ─), and
   // empty lines. This exposes the actual prompt or content line for detection.
@@ -493,6 +500,11 @@ function classifyTerminalOutput(terminalOutput: string): ActivityState {
   // The ❯ is Claude Code's prompt character.
   if (/^[❯>$#]\s*$/.test(lastLine)) return "idle";
 
+  // Claude Code shows inline suggestions after the prompt when idle, e.g.
+  // "❯ check CI status on the PR". Distinguish from active processing by
+  // checking the status bar: no "esc to interrupt" = idle with suggestion.
+  if (/^[❯>]\s+/.test(lastLine) && !hasEscToInterrupt) return "idle";
+
   // Check the bottom of the buffer for permission prompts BEFORE checking
   // full-buffer active indicators. Historical "Thinking"/"Reading" text in
   // the buffer must not override a current permission prompt at the bottom.