Discord: thread bindings idle + max-age lifecycle (#27845) (thanks @osolmaz)

* refactor discord thread bindings to idle and max-age lifecycle

* fix: migrate legacy thread binding expiry and reduce hot-path disk writes

* refactor: remove remaining thread-binding ttl legacy paths

* fix: harden thread-binding lifecycle persistence

* Discord: fix thread binding types in message/reply paths

* Infra: handle win32 unknown inode in file identity checks

* Infra: relax win32 guarded-open identity checks

* Config: migrate threadBindings ttlHours to idleHours

* Revert "Infra: relax win32 guarded-open identity checks"

This reverts commit de94126771db072ecda6a014e80700310e76df61.

* Revert "Infra: handle win32 unknown inode in file identity checks"

This reverts commit 96fc5ddfb39762aa078d70dd4b4d3754e49a159b.

* Discord: re-read live binding state before sweep unbind

* fix: add changelog note for thread binding lifecycle update (#27845) (thanks @osolmaz)

---------

Co-authored-by: Onur Solmaz <onur@textcortex.com>

src/discord/monitor/message-handler.process.ts

@@ -113,9 +113,14 @@ export async function processDiscordMessage(ctx: DiscordMessagePreflightContext)
   mediaList.push(...forwardedMediaList);
   const text = messageText;
   if (!text) {
-    logVerbose(`discord: drop message ${message.id} (empty content)`);
+    logVerbose("discord: drop message " + message.id + " (empty content)");
     return;
   }
+
+  const boundThreadId = ctx.threadBinding?.conversation?.conversationId?.trim();
+  if (boundThreadId && typeof threadBindings.touchThread === "function") {
+    threadBindings.touchThread({ threadId: boundThreadId });
+  }
   const ackReaction = resolveAckReaction(cfg, route.agentId, {
     channel: "discord",
     accountId,