Problem

• AnyChannel enum dispatch missing 4 Channel trait method forwardings
• Remote channels (Telegram, Discord, Slack) auto-approve destructive confirmations
• Attachment support only in CLI and Telegram
• Markdown rendering inconsistent across channels
• Slack sends raw markdown (incorrect rendering)
• Discord/Slack have no registered slash commands

Goal

Ensure feature parity across channels and fix missing forwarding in AnyChannel.

Audit Reference

.local/audit/006-channel-consistency.md + .local/audit/006-feature-matrix.csv

Key Issues

• CHAN-01: AnyChannel missing send_thinking_chunk, send_stop_hint, send_usage, send_tool_start
• CHAN-02: Remote channel confirmation dialogs (Telegram inline keyboard, etc.)
• CHAN-03: Attachment support in Discord/Slack/TUI
• CHAN-04: Streaming behavior documentation
• CHAN-05: Slash command registration for Discord/Slack
• CHAN-06: Markdown/mrkdwn conversion for Slack

Acceptance Criteria

• AnyChannel forwards all 16 Channel trait methods
• Telegram confirm() uses inline keyboard for destructive operations
• At least one additional channel supports attachments
• All tests pass