feat(telegram): live progress indicator for the remote-control channel

[SergiioB]

What

The Telegram remote-control channel now posts an editable "Thinking…" bubble the moment an owner message lands, updates it live with the turn's activity, and removes it when the reply is ready.

Why

Today the only feedback is the native chatAction: "typing" dots. They are easy to miss and disappear the instant a fast reply lands, so a short answer gives no visible sign the message was received. This adds a clear, persistent acknowledgement that also surfaces what the agent is doing on longer turns.

Behavior

• On message receipt: posts 🤔 Thinking….
• During the turn: edits the bubble with live activity — ⚙️ Working… (step N), 🔧 <tool> (from tool_call_parsed), ✅ <step summary> (from step_finished), 🔁 Repeating <tool> (×N) (from loop_detected).
• On settle: deletes the bubble and posts the reply (or the existing cancel/failure infra message) so the answer stands alone.
• The existing typing-dot keepalive is unchanged and still runs.

Implementation notes

• New TelegramProgressIndicator in inbound-handler.ts, wired into dispatchToRuntime through the existing eventHook.
• Adds an optional deleteMessage to the TelegramApi surface (grammy's bot.api already provides it).
• Pure channel infrastructure: every post/edit/delete is best-effort and serialised through one promise chain. Edits are throttled (~700 ms) with identical-text suppression to stay well under Telegram's per-chat edit rate limits. A fast turn that calls remove() before the initial sendMessage resolves still cleans up the just-posted message.
• No config change; the indicator is always on, matching the always-on typing keepalive. Happy to gate it behind a telegram.* flag if you prefer.

Testing

• All 129 existing Telegram channel tests pass (vitest run src/channels/telegram/), including the 23 inbound-handler tests.
• Running in production on a headless Linux (ARM64) serve deployment against a remote llama-server.

Happy to add a dedicated unit test for the indicator lifecycle and/or put it behind a config flag if that helps merge.