release(v4.6.0): broadcast channels — Signal sender-keys for one-to-many fan-out

Lands the broadcast-channel primitive Prism asked for in
Docs/shade-feature-request-sender-keys.md. The crypto in
@shade/core/sender-keys.ts was already in place; this release wires
it up as a first-class app-facing API, adds the persistence schema
across all six storage backends (memory, sqlite, indexeddb +
encrypted variants), introduces wire type 0x21 in @shade/proto,
and ships Prism's three acceptance tests verbatim.

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

packages/shade-storage-indexeddb/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@shade/storage-indexeddb",
-  "version": "4.5.0",
+  "version": "4.6.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",

packages/shade-storage-indexeddb/src/indexeddb-storage.ts

@@ -9,6 +9,8 @@ import type {
   PersistedStreamState,
   PeerVerification,
   PeerVerificationSource,
+  BroadcastChannelRecord,
+  BroadcastMemberRecord,
 } from '@shade/core';
 import {
   toBase64, fromBase64,
@@ -67,6 +69,11 @@ export class IndexedDBStorage implements StorageProvider {
           db.createObjectStore('peerVerifications', { keyPath: 'peerAddress' });
           db.createObjectStore('peerIdentityVersions', { keyPath: 'peerAddress' });
         }
+        if (oldVersion < 2) {
+          db.createObjectStore('broadcastChannels', { keyPath: 'channelId' });
+          const members = db.createObjectStore('broadcastMembers', { keyPath: ['channelId', 'peerAddress'] });
+          members.createIndex('byChannelId', 'channelId');
+        }
       },
     });
     return new IndexedDBStorage(db);
@@ -296,11 +303,64 @@ export class IndexedDBStorage implements StorageProvider {
     await tx.done;
     return next;
   }
+
+  // ─── Broadcast channels (V4.6) ────────────────────────────
+
+  async saveBroadcastChannel(channel: BroadcastChannelRecord): Promise<void> {
+    await this.db.put('broadcastChannels', channelToRow(channel));
+  }
+
+  async getBroadcastChannel(channelId: string): Promise<BroadcastChannelRecord | null> {
+    const row = await this.db.get('broadcastChannels', channelId);
+    if (!row) return null;
+    return rowToChannel(row);
+  }
+
+  async listBroadcastChannels(): Promise<BroadcastChannelRecord[]> {
+    const rows = await this.db.getAll('broadcastChannels');
+    rows.sort((a, b) => a.createdAt - b.createdAt);
+    return rows.map(rowToChannel);
+  }
+
+  async removeBroadcastChannel(channelId: string): Promise<void> {
+    const tx = this.db.transaction(['broadcastChannels', 'broadcastMembers'], 'readwrite');
+    const memIdx = tx.objectStore('broadcastMembers').index('byChannelId');
+    let cursor = await memIdx.openCursor(IDBKeyRange.only(channelId));
+    while (cursor) {
+      await cursor.delete();
+      cursor = await cursor.continue();
+    }
+    await tx.objectStore('broadcastChannels').delete(channelId);
+    await tx.done;
+  }
+
+  async saveBroadcastMember(member: BroadcastMemberRecord): Promise<void> {
+    await this.db.put('broadcastMembers', { ...member });
+  }
+
+  async getBroadcastMembers(channelId: string): Promise<BroadcastMemberRecord[]> {
+    const rows = await this.db.getAllFromIndex(
+      'broadcastMembers',
+      'byChannelId',
+      IDBKeyRange.only(channelId),
+    );
+    rows.sort((a, b) => a.joinedAt - b.joinedAt);
+    return rows.map((r) => ({
+      channelId: r.channelId,
+      peerAddress: r.peerAddress,
+      joinedAt: r.joinedAt,
+      removedAt: r.removedAt,
+    }));
+  }
+
+  async removeBroadcastMember(channelId: string, peerAddress: string): Promise<void> {
+    await this.db.delete('broadcastMembers', [channelId, peerAddress]);
+  }
 }
 
 // ─── Schema ────────────────────────────────────────────────
 
-const SCHEMA_VERSION = 1;
+const SCHEMA_VERSION = 2;
 
 interface IdentityRow {
   id: 1;
@@ -370,6 +430,27 @@ interface PeerIdentityVersionRow {
   version: number;
 }
 
+interface BroadcastChannelRow {
+  channelId: string;
+  ownerRole: 'sender' | 'receiver';
+  ownerAddress: string;
+  label: string | null;
+  generation: number;
+  chainKey: Uint8Array;
+  iteration: number;
+  signingPublicKey: Uint8Array;
+  signingPrivateKey: Uint8Array | null;
+  createdAt: number;
+  updatedAt: number;
+}
+
+interface BroadcastMemberRow {
+  channelId: string;
+  peerAddress: string;
+  joinedAt: number;
+  removedAt: number | null;
+}
+
 interface ShadeSchema extends DBSchema {
   identity: { key: number; value: IdentityRow };
   config: { key: string; value: ConfigRow };
@@ -393,6 +474,12 @@ interface ShadeSchema extends DBSchema {
   };
   peerVerifications: { key: string; value: PeerVerificationRow };
   peerIdentityVersions: { key: string; value: PeerIdentityVersionRow };
+  broadcastChannels: { key: string; value: BroadcastChannelRow };
+  broadcastMembers: {
+    key: [string, string];
+    value: BroadcastMemberRow;
+    indexes: { byChannelId: string };
+  };
 }
 
 // ─── Helpers ──────────────────────────────────────────────
@@ -415,6 +502,39 @@ function persistedToRow(s: PersistedStreamState): StreamStateRow {
   };
 }
 
+function channelToRow(c: BroadcastChannelRecord): BroadcastChannelRow {
+  return {
+    channelId: c.channelId,
+    ownerRole: c.ownerRole,
+    ownerAddress: c.ownerAddress,
+    label: c.label ?? null,
+    generation: c.generation,
+    chainKey: c.chainKey,
+    iteration: c.iteration,
+    signingPublicKey: c.signingPublicKey,
+    signingPrivateKey: c.signingPrivateKey ?? null,
+    createdAt: c.createdAt,
+    updatedAt: c.updatedAt,
+  };
+}
+
+function rowToChannel(r: BroadcastChannelRow): BroadcastChannelRecord {
+  const out: BroadcastChannelRecord = {
+    channelId: r.channelId,
+    ownerRole: r.ownerRole,
+    ownerAddress: r.ownerAddress,
+    generation: r.generation,
+    chainKey: r.chainKey,
+    iteration: r.iteration,
+    signingPublicKey: r.signingPublicKey,
+    createdAt: r.createdAt,
+    updatedAt: r.updatedAt,
+  };
+  if (r.label !== null) out.label = r.label;
+  if (r.signingPrivateKey !== null) out.signingPrivateKey = r.signingPrivateKey;
+  return out;
+}
+
 function rowToPersisted(r: StreamStateRow): PersistedStreamState {
   const out: PersistedStreamState = {
     streamId: r.streamId,