Approval button clicks (Block Kit actions in Slack, CallbackQuery in
Telegram) bypass the normal message authorization flow in gateway/run.py.
Any workspace/group member who can see the approval message could click
Approve to authorize dangerous commands.

Read SLACK_ALLOWED_USERS / TELEGRAM_ALLOWED_USERS env vars directly in
the approval handlers. When an allowlist is configured and the clicking
user is not in it, the click is silently ignored (Slack) or answered
with an error (Telegram). Wildcard '*' permits all users. When no
allowlist is configured, behavior is unchanged (open access).

Based on the idea from PR #6735 by maymuneth, reimplemented to use the
existing env-var-based authorization system rather than a nonexistent
_allowed_user_ids adapter attribute.

…pport

Port the mention gating pattern from Telegram, Discord, WhatsApp, and
Matrix adapters to the Slack platform adapter.

- Add _slack_require_mention() with explicit-false parsing and env var
  fallback (SLACK_REQUIRE_MENTION)
- Add _slack_free_response_channels() with env var fallback
  (SLACK_FREE_RESPONSE_CHANNELS)
- Replace hardcoded mention check with configurable gating logic
- Bridge slack config.yaml settings to env vars
- Bridge free_response_channels through the generic platform bridging loop
- Add 26 tests covering config parsing, env fallback, gating logic

Config usage:
  slack:
    require_mention: false
    free_response_channels:
      - "C0AQWDLHY9M"

Default behavior unchanged: channels require @mention (backward compatible).

Based on PR #5885 by dorukardahan, cherry-picked and adapted to current main.

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic***
handling, HTML entity double-escaping (&), Wikipedia URL parens
truncation, and step numbering format. Also adds format_message to the
tool-layer _send_to_platform for consistent formatting across all
delivery paths.

Changes:
- Protect Slack entities (<@user>, <https://...|label>, <!here>) from
  escaping passes
- Protect blockquote > markers before HTML entity escaping
- Unescape-before-escape for idempotent HTML entity handling
- ***bold italic*** → *_text_* conversion (before **bold** pass)
- URL regex upgraded to handle balanced parentheses
- mrkdwn:True flag on chat_postMessage payloads
- format_message applied in edit_message and send_message_tool
- 52 new tests (format, edit, streaming, splitting, tool chunking)
- Use reversed(dict) idiom for placeholder restoration

Based on PR #3715 by dashed, cherry-picked onto current main.

Three modes: "none" (default, backward-compatible), "mentions" (accept
bot messages only when they @mention us), "all" (accept all bot messages
except our own, to prevent echo loops).

Configurable via:
  slack:
    allow_bots: mentions
Or env var: SLACK_ALLOW_BOTS=mentions

Self-message guard always active regardless of mode.

Based on PR #3200 by Mibayy, adapted to current main with config.yaml
bridging support.

- Treat mpim (multi-party IM / group DM) channels as DMs — no @mention
  required, continuous session like 1:1 DMs
- Only add 👀/✅ reactions when bot is directly addressed (DM or
  @mention). In listen-all channels (require_mention=false) reacting
  to every message would be noisy.

Based on PR #4633 by gunpowder-client-vm, adapted to current main.

…hing

- Add _ThreadContextCache dataclass for caching fetched context (60s TTL)
- Add exponential backoff retry for conversations.replies 429 rate limits
  (Tier 3, ~50 req/min)
- Only fetch context when no active session exists (guard at call site)
  to prevent duplication across turns
- Hoist bot_uid lookup outside the per-message loop
- Clearer header text for injected thread context

Based on PR #6162 by jarvisxyz, cherry-picked onto current main.