fix(telegram): convert Markdown tables to bullet lists

[mauruk]

Summary

• Telegram does not render Markdown tables — pipes and dashes show up raw, making structured output illegible.
• _convert_table() rewrites table blocks to **header:** value bullets before MarkdownV2 escaping.
• Plain text and inline pipes outside tables are untouched.

Problem

When the agent produces tables (comparisons, specs, schedules) for Telegram DMs/topics, users see this:

| Feature | Hook | Provider |
|---------|------|----------|
| Latency | ~500ms | ~0ms |
| Shutdown | hard kill | graceful |

…rendered literally. Zero visual structure.

Fix

In TelegramAdapter.format_text() (the hook before MarkdownV2 escaping), walk the text line-by-line. When a block of |…| rows is detected, optionally followed by a separator |---|…|:

1. Parse the header row (cells between pipes).
2. Skip the separator.
3. For each data row, emit:
   • A blank line
   • For each (header, cell): • **header:** cell (one line each)

Everything else passes through unchanged.

Test plan

• Tables with 2–6 columns render as readable bullets
• Tables with alignment hints (:---, ---:, :---:) handled (separator-row regex is permissive)
• Text with inline pipes outside tables (a | b in prose) not rewritten
• Mixed content (prose + multiple tables) preserves order
• Empty cells skipped cleanly
• Running in production on a private Hetzner instance since early April 2026 — zero table-related complaints since.

Note

Patch has been carried locally in production for ~10 days. Opening upstream so it doesn't need to be rebased on every release.

🤖 Generated with Claude Code

[alt-glitch]

Related to #14160 (feature request) and competing with #14431 (similar approach: row-group bullet formatting). Please coordinate.

[teknium1]

Thanks for the contribution and for running this in production — the approach is solid and the problem was real.

This is an automated hermes-sweeper review.

The underlying bug is already fixed on main. PR #11794 (commit 036dacf65, merged April 17 2026 — one day after this PR was opened) added _wrap_markdown_tables() to gateway/platforms/telegram.py and wires it into format_message() at the same pre-escaping step this PR targets. Telegram now renders pipe tables as monospace fenced code blocks rather than raw escaped text.

• Implementation: gateway/platforms/telegram.py, _wrap_markdown_tables() (~line 147) + call at ~line 2062
• Merged commit: 036dacf6592dac36a57a3d26187039fb3b1a37a0

The rendering approach differs (code fences vs bullet lists), and if bullet-group formatting is preferred over code-fence wrapping, the right path forward is PR #14431 which explicitly proposes that upgrade and closes issue #14160. Please feel free to coordinate there.