Message Logger: show logged edits and deletions from telegram-panel [no bump]

Keeps deleted messages (75% opacity, red icon-pack trash icon), restores
logged messages deleted while away, reports deletions, and shows edit
history as a mock chat (Edit history in the message menu, Open topic).
Message links and history open as any signed-in account with access.
Per-master API tokens; chat state synced per checked range with an hour's
validity, cached in SQLite with a configurable lifetime.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -1,4 +1,40 @@
-# exteraGram Plugin Base
+# Message Logger (exteraGram plugin)
+
+Shows what a [telegram-panel](../../telegram-panel) message logger saved, natively in chats:
+
+- messages others delete stay (the delete updates are dropped), at 75% opacity with a red trash
+  icon (from the active icon pack) in the time row, and are reported to the server;
+- logged messages deleted while the app was closed (or never seen deleted by the server, e.g.
+  bot-logged chats) are confirmed with Telegram, reported, and restored from the logger copy;
+- *Edit history* in the message menu (right above Forward, for edited messages) opens every
+  version as a mock chat — also on the logger groups' own posts — with an *Open topic* button
+  for the history topic in the activity group. Versions and their media are read from the activity group through
+  a signed-in account that can (the current one, the master, or any member); otherwise the
+  server's text is shown and media are marked unavailable;
+- message links into a chat the current account isn't in (e.g. a log post's "Message" link)
+  open that chat as a signed-in account that is in it; going back returns to your account.
+  Every signed-in account's chats are cached client-side for this.
+
+The server only points at copies (logger/activity group message ids); the client reads them
+through its own session, so the account must be a member of those groups.
+
+The server is asked about a chat only when needed: when it wasn't checked within the last hour
+(from the oldest loaded message on; the answer replaces the chat's cached marks), when older
+history is loaded past the checked range (that part only), or after an edit/delete event in the
+chat. Answers hold at most 100 marks (edited/deleted) and 100 missing ids, newest first. Marks
+are cached per chat in the plugin's SQLite (`state.db`, no size cap), so a chat opened again —
+even offline — shows them at once, and deleted messages are restored from the cache. An expired
+chat keeps its cache until the next successful check, which replaces it and starts over. Cached
+answers older than *Cache lifetime* (1/7/30/90/365 days or never; 30 by default) are removed,
+checked once a day (from local midnight) and when the setting changes.
+
+Setup: in the panel create a token per master — the account owning the logger groups —
+(Settings → API Tokens); in the plugin settings enter the panel URL and the tokens (separated by
+spaces), then *Test connection*. Any Telegram account can use a token. Diagnostics: see `docs/sdk-notes.md` (gotchas section).
+
+The rest of this README describes the build toolchain this repo came from (pluginBase).
+
+## Plugin base toolchain
 
 A build toolchain and ADB automation for writing [exteraGram](https://exteragram.app) plugins
 as ordinary multi-file Python projects instead of hand-maintaining one giant `.py` file.