feat(tools): fabric-send-message + fabric-channel-list + fabric-message-history

Plugin previously had no way for an agent to send text into a specific
channel proactively — outbound went only through the channel-reply
path (responds to the channel that woke the agent). discussion-complete
internally called client.postMessage but only for the close-time
summary, no general-purpose surface.

Three new tools (+ declare existing fabric-canvas / fabric-channel that
were registered but missing from contracts.tools so agents couldn't
see them per the openclaw plugin contract):

  * fabric-send-message {guildNodeId, channelId, content}
      → {ok, messageId, seq}
    Author = calling agent. Use for ARD broadcasts, follow-ups in a
    different channel, etc.

  * fabric-channel-list {guildNodeId, nameFilter?, xType?, includeClosed?}
      → {ok, count, channels[]}
    Backend filters to public + member channels; nameFilter is client-
    side case-insensitive substring; xType / includeClosed apply post-
    fetch. Returns id/name/xType/lastSeq so callers can pipe into the
    other tools.

  * fabric-message-history {guildNodeId, channelId, seqFrom?, seqTo?, limit?}
      → {ok, page, messages[]}
    Tail-by-default: omit seqFrom/seqTo and the tool fetches the
    channel head from listChannels then asks for [head-limit+1, head].
    Limit default 20, max 200. Backend rejects non-participants.

Plus 3 supporting client methods (listChannels, listMessages — both
GET via existing req helper).

contracts.tools updated to declare these 5 (3 new + 2 previously-
silent ones). Verified earlier in sim restart logs: openclaw warned
'plugin tool is undeclared (fabric): fabric-canvas / fabric-channel'
so agents couldn't use them despite registerTool firing.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/fabric-client.ts

@@ -190,6 +190,76 @@ export class FabricClient {
   removeCanvas(endpoint: string, token: string, channelId: string): Promise<unknown> {
     return this.req('DELETE', this.canvasUrl(endpoint, channelId), token);
   }
+
+  // ---- channel discovery + message read (used by the agent-facing
+  // fabric-channel-list / fabric-message-history tools) ----
+
+  /**
+   * List channels in a guild visible to the calling user. Backend
+   * filters to public + channels the user is a member of.
+   */
+  listChannels(
+    guildEndpoint: string,
+    guildToken: string,
+    guildNodeId: string,
+  ): Promise<Array<{
+    id: string;
+    guildId: string;
+    name: string;
+    xType: string;
+    kind: string;
+    isPublic: boolean;
+    closed: boolean;
+    lastSeq: number;
+    createdAt: string;
+  }>> {
+    return this.req(
+      'GET',
+      `${guildEndpoint}/api/channels?guildId=${encodeURIComponent(guildNodeId)}`,
+      guildToken,
+    );
+  }
+
+  /**
+   * Page through a channel's message history by `seq`.
+   *
+   * Backend defaults: 50 / call, max 200. The `seq` field starts at 1
+   * per channel; pass `seqFrom=channel.lastSeq - N + 1` to get the
+   * tail. Page metadata in the response describes what to ask next.
+   */
+  listMessages(
+    guildEndpoint: string,
+    guildToken: string,
+    channelId: string,
+    opts: { seqFrom?: number; seqTo?: number; limit?: number } = {},
+  ): Promise<{
+    items: Array<{
+      messageId: string;
+      seq: number;
+      content: string;
+      authorUserId: string;
+      createdAt: string;
+      editedAt: string | null;
+      deletedAt: string | null;
+      isDeleted: boolean;
+    }>;
+    page: {
+      seqFrom: number;
+      seqTo: number;
+      limit: number;
+      returned: number;
+      hasMore: boolean;
+      nextExpectedSeq: number;
+      highestCommittedSeq: number;
+    };
+  }> {
+    const qs = new URLSearchParams();
+    if (opts.seqFrom !== undefined) qs.set('seq_from', String(opts.seqFrom));
+    if (opts.seqTo !== undefined) qs.set('seq_to', String(opts.seqTo));
+    if (opts.limit !== undefined) qs.set('limit', String(opts.limit));
+    const url = `${guildEndpoint}/api/channels/${channelId}/messages` + (qs.toString() ? `?${qs}` : '');
+    return this.req('GET', url, guildToken);
+  }
 }
 
 export type CanvasFormat = 'md' | 'html' | 'text';