feat(feishu): replace built-in SDK with community plugin

Replace the built-in Feishu SDK with the community-maintained
clawdbot-feishu plugin by @m1heng.

Changes:
- Remove src/feishu/ directory (19 files)
- Remove src/channels/plugins/outbound/feishu.ts
- Remove src/channels/plugins/normalize/feishu.ts
- Remove src/config/types.feishu.ts
- Remove feishu exports from plugin-sdk/index.ts
- Remove FeishuConfig from types.channels.ts

New features in community plugin:
- Document tools (read/create/edit Feishu docs)
- Wiki tools (navigate/manage knowledge base)
- Drive tools (folder/file management)
- Bitable tools (read/write table records)
- Permission tools (collaborator management)
- Emoji reactions support
- Typing indicators
- Rich media support (bidirectional image/file transfer)
- @mention handling
- Skills for feishu-doc, feishu-wiki, feishu-drive, feishu-perm

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

extensions/feishu/src/mention.ts

@@ -0,0 +1,118 @@
+import type { FeishuMessageEvent } from "./bot.js";
+
+/**
+ * Mention target user info
+ */
+export type MentionTarget = {
+  openId: string;
+  name: string;
+  key: string; // Placeholder in original message, e.g. @_user_1
+};
+
+/**
+ * Extract mention targets from message event (excluding the bot itself)
+ */
+export function extractMentionTargets(
+  event: FeishuMessageEvent,
+  botOpenId?: string,
+): MentionTarget[] {
+  const mentions = event.message.mentions ?? [];
+
+  return mentions
+    .filter((m) => {
+      // Exclude the bot itself
+      if (botOpenId && m.id.open_id === botOpenId) return false;
+      // Must have open_id
+      return !!m.id.open_id;
+    })
+    .map((m) => ({
+      openId: m.id.open_id!,
+      name: m.name,
+      key: m.key,
+    }));
+}
+
+/**
+ * Check if message is a mention forward request
+ * Rules:
+ * - Group: message mentions bot + at least one other user
+ * - DM: message mentions any user (no need to mention bot)
+ */
+export function isMentionForwardRequest(event: FeishuMessageEvent, botOpenId?: string): boolean {
+  const mentions = event.message.mentions ?? [];
+  if (mentions.length === 0) return false;
+
+  const isDirectMessage = event.message.chat_type === "p2p";
+  const hasOtherMention = mentions.some((m) => m.id.open_id !== botOpenId);
+
+  if (isDirectMessage) {
+    // DM: trigger if any non-bot user is mentioned
+    return hasOtherMention;
+  } else {
+    // Group: need to mention both bot and other users
+    const hasBotMention = mentions.some((m) => m.id.open_id === botOpenId);
+    return hasBotMention && hasOtherMention;
+  }
+}
+
+/**
+ * Extract message body from text (remove @ placeholders)
+ */
+export function extractMessageBody(text: string, allMentionKeys: string[]): string {
+  let result = text;
+
+  // Remove all @ placeholders
+  for (const key of allMentionKeys) {
+    result = result.replace(new RegExp(key.replace(/[.*+?^${}()|[\]\\]/g, "\\$&"), "g"), "");
+  }
+
+  return result.replace(/\s+/g, " ").trim();
+}
+
+/**
+ * Format @mention for text message
+ */
+export function formatMentionForText(target: MentionTarget): string {
+  return `<at user_id="${target.openId}">${target.name}</at>`;
+}
+
+/**
+ * Format @everyone for text message
+ */
+export function formatMentionAllForText(): string {
+  return `<at user_id="all">Everyone</at>`;
+}
+
+/**
+ * Format @mention for card message (lark_md)
+ */
+export function formatMentionForCard(target: MentionTarget): string {
+  return `<at id=${target.openId}></at>`;
+}
+
+/**
+ * Format @everyone for card message
+ */
+export function formatMentionAllForCard(): string {
+  return `<at id=all></at>`;
+}
+
+/**
+ * Build complete message with @mentions (text format)
+ */
+export function buildMentionedMessage(targets: MentionTarget[], message: string): string {
+  if (targets.length === 0) return message;
+
+  const mentionParts = targets.map((t) => formatMentionForText(t));
+  return `${mentionParts.join(" ")} ${message}`;
+}
+
+/**
+ * Build card content with @mentions (Markdown format)
+ */
+export function buildMentionedCardContent(targets: MentionTarget[], message: string): string {
+  if (targets.length === 0) return message;
+
+  const mentionParts = targets.map((t) => formatMentionForCard(t));
+  return `${mentionParts.join(" ")} ${message}`;
+}