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 de94126771.

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

This reverts commit 96fc5ddfb3.

* 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/native-command.model-picker.test.ts

@@ -179,7 +179,8 @@ function createBoundThreadBindingManager(params: {
 }): ThreadBindingManager {
   return {
     accountId: params.accountId,
-    getSessionTtlMs: () => 24 * 60 * 60 * 1000,
+    getIdleTimeoutMs: () => 24 * 60 * 60 * 1000,
+    getMaxAgeMs: () => 0,
     getByThreadId: (threadId: string) =>
       threadId === params.threadId
         ? {
@@ -191,11 +192,15 @@ function createBoundThreadBindingManager(params: {
             agentId: params.agentId,
             boundBy: "system",
             boundAt: Date.now(),
+            lastActivityAt: Date.now(),
+            idleTimeoutMs: 24 * 60 * 60 * 1000,
+            maxAgeMs: 0,
           }
         : undefined,
     getBySessionKey: () => undefined,
     listBySessionKey: () => [],
     listBindings: () => [],
+    touchThread: () => null,
     bindTarget: async () => null,
     unbindThread: () => null,
     unbindBySessionKey: () => [],