feat(telegram): wire replyToMode config, add forum topic support, fix messaging tool duplicates

Changes:
- Default replyToMode from "off" to "first" for better threading UX
- Add messageThreadId and replyToMessageId params for forum topic support
- Add messaging tool duplicate detection to suppress redundant block replies
- Add sendMessage action to telegram tool schema
- Add @grammyjs/types devDependency for proper TypeScript typing
- Remove @ts-nocheck and fix all type errors in send.ts
- Add comprehensive docs/telegram.md documentation
- Add PR-326-REVIEW.md with John Carmack-level code review

Test coverage:
- normalizeTextForComparison: 5 cases
- isMessagingToolDuplicate: 7 cases
- sendMessageTelegram thread params: 5 cases
- handleTelegramAction sendMessage: 4 cases
- Forum topic isolation: 4 cases

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

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

src/agents/pi-embedded-helpers.ts

@@ -346,3 +346,50 @@ export function validateGeminiTurns(messages: AgentMessage[]): AgentMessage[] {
 
   return result;
 }
+
+// ── Messaging tool duplicate detection ──────────────────────────────────────
+// When the agent uses a messaging tool (telegram, discord, slack, sessions_send)
+// to send a message, we track the text so we can suppress duplicate block replies.
+// The LLM sometimes elaborates or wraps the same content, so we use substring matching.
+
+const MIN_DUPLICATE_TEXT_LENGTH = 10;
+
+/**
+ * Normalize text for duplicate comparison.
+ * - Trims whitespace
+ * - Lowercases
+ * - Strips emoji (Emoji_Presentation and Extended_Pictographic)
+ * - Collapses multiple spaces to single space
+ */
+export function normalizeTextForComparison(text: string): string {
+  return text
+    .trim()
+    .toLowerCase()
+    .replace(/\p{Emoji_Presentation}|\p{Extended_Pictographic}/gu, "")
+    .replace(/\s+/g, " ")
+    .trim();
+}
+
+/**
+ * Check if a text is a duplicate of any previously sent messaging tool text.
+ * Uses substring matching to handle LLM elaboration (e.g., wrapping in quotes,
+ * adding context, or slight rephrasing that includes the original).
+ */
+export function isMessagingToolDuplicate(
+  text: string,
+  sentTexts: string[],
+): boolean {
+  if (sentTexts.length === 0) return false;
+  const normalized = normalizeTextForComparison(text);
+  if (!normalized || normalized.length < MIN_DUPLICATE_TEXT_LENGTH)
+    return false;
+  return sentTexts.some((sent) => {
+    const normalizedSent = normalizeTextForComparison(sent);
+    if (!normalizedSent || normalizedSent.length < MIN_DUPLICATE_TEXT_LENGTH)
+      return false;
+    // Substring match: either text contains the other
+    return (
+      normalized.includes(normalizedSent) || normalizedSent.includes(normalized)
+    );
+  });
+}