feat: add presentation discussion branches

web/apps/console/src/presentation/DiscussionIndex.tsx

@@ -0,0 +1,52 @@
+import { discussionBranches, findScene, type MainSceneId } from "./storyboard.js";
+
+type DiscussionIndexProps = {
+  readonly onSelect: (branchId: string) => void;
+};
+
+type BranchGroup = {
+  readonly parentSceneId: MainSceneId;
+  readonly sceneTitle: string;
+  readonly branches: typeof discussionBranches[number][];
+};
+
+const groupByParentScene = (): readonly BranchGroup[] => {
+  const groups = new Map<string, BranchGroup>();
+  for (const branch of discussionBranches) {
+    let group = groups.get(branch.parentSceneId);
+    if (!group) {
+      const scene = findScene(branch.parentSceneId);
+      group = {
+        parentSceneId: branch.parentSceneId,
+        sceneTitle: scene?.title ?? branch.parentSceneId,
+        branches: [],
+      };
+      groups.set(branch.parentSceneId, group);
+    }
+    group.branches.push(branch);
+  }
+  return Array.from(groups.values());
+};
+
+export const DiscussionIndex = ({ onSelect }: DiscussionIndexProps) => {
+  const groups = groupByParentScene();
+  return (
+    <div className="discussion-index" role="dialog" aria-label="discussion topics">
+      <h2>Discussion Topics</h2>
+      {groups.map((group) => (
+        <section key={group.parentSceneId}>
+          <h3>{group.sceneTitle}</h3>
+          <ul>
+            {group.branches.map((branch) => (
+              <li key={branch.id}>
+                <button type="button" onClick={() => onSelect(branch.id)}>
+                  {branch.title}
+                </button>
+              </li>
+            ))}
+          </ul>
+        </section>
+      ))}
+    </div>
+  );
+};

web/apps/console/src/presentation/DiscussionPanel.tsx

@@ -0,0 +1,41 @@
+import { findDiscussionBranch, findScene } from "./storyboard.js";
+
+type DiscussionPanelProps = {
+  readonly branchId: string;
+  readonly onClose: () => void;
+};
+
+export const DiscussionPanel = ({ branchId, onClose }: DiscussionPanelProps) => {
+  const branch = findDiscussionBranch(branchId);
+  if (!branch) return null;
+
+  const parentScene = findScene(branch.parentSceneId);
+
+  return (
+    <div className="discussion-panel" role="dialog" aria-label={branch.title}>
+      <header>
+        <h2>{branch.title}</h2>
+        <span className="discussion-panel__badge">{branch.claimClass}</span>
+      </header>
+      <p className="discussion-panel__evidence">{branch.evidencePointer}</p>
+      <p className="discussion-panel__summary">{branch.summary}</p>
+      {branchId === "hosted-automation" && (
+        <p className="discussion-panel__detail">
+          A future scheduler could trigger a workflow that launches a verified headless
+          coding-agent command with a stored prompt. lda.chat does not implement that
+          trigger or scheduler in the submitted scope.
+        </p>
+      )}
+      {branchId === "mcp-agent-scale" && (
+        <p className="discussion-panel__detail">
+          <a href="https://modelcontextprotocol.io/" target="_blank" rel="noopener noreferrer">Model Context Protocol</a> ·{" "}
+          <a href="https://developers.cloudflare.com/workers-ai/configuration/code-mode/" target="_blank" rel="noopener noreferrer">Cloudflare Code Mode</a>
+          {" "}— both are external context.
+        </p>
+      )}
+      <button type="button" onClick={onClose} className="discussion-panel__return">
+        Return to {parentScene?.title ?? "scene"}
+      </button>
+    </div>
+  );
+};

web/apps/console/src/presentation/PresentationRoute.test.tsx

@@ -62,4 +62,23 @@ describe("PresentationRoute", () => {
     expect(screen.getAllByText(/selectWorkflowNode/i).length).toBeGreaterThanOrEqual(2);
     expect(await screen.findByRole("dialog", { name: /issue review/i })).toBeInTheDocument();
   });
+
+  it("opens a positioning branch and returns to the exact originating beat", async () => {
+    window.location.hash = "#scene/positioning/lda-position";
+    render(<PresentationRoute />);
+
+    await userEvent.click(screen.getByRole("button", { name: /open discussion topics/i }));
+    await userEvent.click(screen.getByRole("button", { name: /hosted automation/i }));
+    expect(window.location.hash).toBe("#discuss/hosted-automation");
+
+    await userEvent.click(screen.getByRole("button", { name: /return to positioning/i }));
+    expect(window.location.hash).toBe("#scene/positioning/lda-position");
+  });
+
+  it("uses the parent scene as return location for a directly linked branch", async () => {
+    window.location.hash = "#discuss/mcp-agent-scale";
+    render(<PresentationRoute />);
+    await userEvent.click(screen.getByRole("button", { name: /return to positioning/i }));
+    expect(window.location.hash).toBe("#scene/positioning/landscape");
+  });
 });

web/apps/console/src/presentation/PresentationRoute.tsx

@@ -137,6 +137,16 @@ export const PresentationRoute = () => {
     [],
   );
 
+  const handleOpenDiscussion = useCallback(
+    (branchId: string) => dispatch({ type: "open_discussion", branchId }),
+    [],
+  );
+
+  const handleCloseDiscussion = useCallback(
+    () => dispatch({ type: "close_discussion" }),
+    [],
+  );
+
   return (
     <main className="presentation-route" aria-label="lda.chat presentation">
       <PresentationStage
@@ -150,6 +160,8 @@ export const PresentationRoute = () => {
         selectNode={(nodeId) => dispatch({ type: "select_node", nodeId })}
         openEvidence={() => dispatch({ type: "set_evidence_mode", mode: "open" })}
         closeOverlay={() => dispatch({ type: "close_overlay" })}
+        openDiscussion={handleOpenDiscussion}
+        closeDiscussion={handleCloseDiscussion}
       />
       <button
         type="button"

web/apps/console/src/presentation/PresentationStage.tsx

@@ -1,13 +1,16 @@
+import { useState } from "react";
 import type { EvidenceRecord } from "../app/state.js";
 import type { AgentMessage } from "../demo/agent/events.js";
 import { SceneBody } from "./SceneBody.js";
 import { SceneRail } from "./SceneRail.js";
+import { DiscussionIndex } from "./DiscussionIndex.js";
+import { DiscussionPanel } from "./DiscussionPanel.js";
 import { EvidenceDrawer } from "./EvidenceDrawer.js";
 import { OperatorChat } from "./OperatorChat.js";
 import type { PresentationState } from "./presentation-state.js";
 import { compositionForState } from "./presentation-state.js";
 import type { DemoTimelineController } from "../demo/useDemoTimeline.js";
-import type { MainLocation, PresentationLocation } from "./storyboard.js";
+import { discussionBranches, findScene, type PresentationLocation } from "./storyboard.js";
 
 type PresentationStageProps = {
   readonly state: PresentationState;
@@ -20,6 +23,8 @@ type PresentationStageProps = {
   readonly selectNode: (nodeId: string) => void;
   readonly openEvidence: () => void;
   readonly closeOverlay: () => void;
+  readonly openDiscussion: (branchId: string) => void;
+  readonly closeDiscussion: () => void;
 };
 
 export const PresentationStage = ({
@@ -33,8 +38,17 @@ export const PresentationStage = ({
   selectNode,
   openEvidence,
   closeOverlay,
+  openDiscussion,
+  closeDiscussion,
 }: PresentationStageProps) => {
   const composition = compositionForState(state);
+  const [indexOpen, setIndexOpen] = useState(false);
+
+  const isMainScene = state.location.kind === "main";
+  const currentScene = isMainScene ? findScene(state.location.sceneId) : null;
+  const hasBranches = currentScene
+    ? discussionBranches.some((b) => b.parentSceneId === currentScene.id)
+    : false;
 
   return (
     <div
@@ -47,12 +61,35 @@ export const PresentationStage = ({
         <OperatorChat state={state} messages={messages} onApprove={onApprove} onDeny={onDeny} />
       </aside>
       <section className="presentation-stage__primary" aria-label="primary presentation region">
-        <SceneBody
-          location={state.location}
-          demo={demo}
-          selectedNodeId={state.selectedNodeId}
-          selectNode={selectNode}
-        />
+        {state.location.kind === "discussion" ? (
+          <DiscussionPanel branchId={state.location.branchId} onClose={closeDiscussion} />
+        ) : (
+          <>
+            <SceneBody
+              location={state.location}
+              demo={demo}
+              selectedNodeId={state.selectedNodeId}
+              selectNode={selectNode}
+            />
+            {hasBranches && (
+              <button
+                type="button"
+                className="presentation-stage__discussion-toggle"
+                onClick={() => setIndexOpen(true)}
+              >
+                Open discussion topics
+              </button>
+            )}
+          </>
+        )}
+        {indexOpen && (
+          <DiscussionIndex
+            onSelect={(branchId) => {
+              setIndexOpen(false);
+              openDiscussion(branchId);
+            }}
+          />
+        )}
         <p className="presentation-stage__mode">
           {demo.state.mode === "replay" ? "Replay" : "Live"} · {demo.state.phase}
         </p>

web/apps/console/src/presentation/presentation-state.ts

@@ -136,9 +136,13 @@ export const presentationReducer = (
     case "jump_hash": {
       const parsed = locationFromHash(action.hash);
       if (parsed.kind === "main") {
-        return { ...state, location: clampMainLocation(parsed) };
+        return { ...state, location: clampMainLocation(parsed), discussionReturn: null };
       }
-      return { ...state, location: parsed };
+      const branch = findDiscussionBranch(parsed.branchId);
+      const returnLoc = branch
+        ? firstBeatOfScene(branch.parentSceneId) ?? defaultMainLocation
+        : defaultMainLocation;
+      return { ...state, location: parsed, discussionReturn: returnLoc };
     }
     case "open_discussion": {
       const branch = findDiscussionBranch(action.branchId);