Bug Description

Plugin approval buttons on Telegram don't work. There are two independent issues:

Issue 1: TelegramExecApprovalHandler missing plugin approval events

TelegramExecApprovalHandler.handleGatewayEvent() only handles exec.approval.requested/resolved, silently ignoring plugin.approval.requested/resolved. Discord's handler supports all four. Fix in PR #57340 commit 1.

Issue 2: Grammy runner sequentializer deadlocks callback_query processing

Even with the handler fix, clicking approval buttons does nothing. The @grammyjs/runner sequentializer processes all updates for a chat sequentially. When the agent turn is blocked waiting for approval, the callback_query from clicking the button is queued behind it at the runner level — the bot's callback handler never executes.

Exec approvals avoid this because they use a dedicated Unix socket (`exec-approvals.sock`), bypassing the Telegram update pipeline entirely.

Recommended fix: Add a pre-sequentializer middleware that intercepts approval `callback_query` updates (matching `APPROVE_CALLBACK_DATA_RE`) and resolves them directly via the gateway client, before they enter the per-chat sequential queue.

Steps to Reproduce

1. Install a plugin that returns `requireApproval` from `before_tool_call` hook
2. Configure `channels.telegram.execApprovals` with `enabled: true` and approver user ID
3. Configure `approvals.plugin.enabled: true`
4. Trigger a tool call that requires plugin approval via Telegram
5. Click "Allow Once" button

Expected Behavior

Approval resolves immediately, tool proceeds.

Actual Behavior

• Button shows "loading" briefly, nothing happens
• Agent hangs until approval timeout (300s default)
• After timeout: tool is denied

Root Cause Analysis

Handler (Issue 1): `extensions/telegram/src/exec-approvals-handler.ts` line 361 — `handleGatewayEvent` only matches `exec.approval.*` events. Compare with Discord at `extensions/discord/src/monitor/exec-approvals.ts` line 665 which handles both.

Sequentializer (Issue 2): The Grammy runner queues all updates per chat. The agent message update holds the chat lock while waiting for approval. The callback_query for the same chat is queued behind it. Confirmed by adding a log at the very first line of the callback_query handler — it never executes during an active approval wait.

Environment

• OpenClaw: 2026.3.28
• Channel: Telegram (Bot API, Grammy + @grammyjs/runner)
• Plugin: ClawClip (returns `requireApproval` from `before_tool_call`)