feat: config-gated /verbose command for messaging gateway (#3262)

* feat: config-gated /verbose command for messaging gateway

Add gateway_config_gate field to CommandDef, allowing cli_only commands
to be conditionally available in the gateway based on a config value.

- CommandDef gains gateway_config_gate: str | None — a config dotpath
  that, when truthy, overrides cli_only for gateway surfaces
- /verbose uses gateway_config_gate='display.tool_progress_command'
- Default is off (cli_only behavior preserved)
- When enabled, /verbose cycles tool_progress mode (off/new/all/verbose)
  in the gateway, saving to config.yaml — same cycle as the CLI
- Gateway helpers (help, telegram menus, slack mapping) dynamically
  check config to include/exclude config-gated commands
- GATEWAY_KNOWN_COMMANDS always includes config-gated commands so
  the gateway recognizes them and can respond appropriately
- Handles YAML 1.1 bool coercion (bare 'off' parses as False)
- 8 new tests for the config gate mechanism + gateway handler

* docs: document gateway_config_gate and /verbose messaging support

- AGENTS.md: add gateway_config_gate to CommandDef fields
- slash-commands.md: note /verbose can be enabled for messaging, update Notes
- configuration.md: add tool_progress_command to display section + usage note
- cli.md: cross-link to config docs for messaging enablement
- messaging/index.md: show tool_progress_command in config snippet
- plugins.md: add gateway_config_gate to register_command parameter table

website/docs/reference/slash-commands.md

@@ -46,7 +46,7 @@ Type `/` in the CLI to open the autocomplete menu. Built-in commands are case-in
 | `/provider` | Show available providers and current provider |
 | `/prompt` | View/set custom system prompt |
 | `/personality` | Set a predefined personality |
-| `/verbose` | Cycle tool progress display: off → new → all → verbose |
+| `/verbose` | Cycle tool progress display: off → new → all → verbose. Can be [enabled for messaging](#notes) via config. |
 | `/reasoning` | Manage reasoning effort and display (usage: /reasoning [level\|show\|hide]) |
 | `/skin` | Show or change the display skin/theme |
 | `/voice [on\|off\|tts\|status]` | Toggle CLI voice mode and spoken playback. Recording uses `voice.record_key` (default: `Ctrl+B`). |
@@ -125,7 +125,8 @@ The messaging gateway supports the following built-in commands inside Telegram,
 
 ## Notes
 
-- `/skin`, `/tools`, `/toolsets`, `/browser`, `/config`, `/prompt`, `/cron`, `/skills`, `/platforms`, `/paste`, `/verbose`, `/statusbar`, and `/plugins` are **CLI-only** commands.
+- `/skin`, `/tools`, `/toolsets`, `/browser`, `/config`, `/prompt`, `/cron`, `/skills`, `/platforms`, `/paste`, `/statusbar`, and `/plugins` are **CLI-only** commands.
+- `/verbose` is **CLI-only by default**, but can be enabled for messaging platforms by setting `display.tool_progress_command: true` in `config.yaml`. When enabled, it cycles the `display.tool_progress` mode and saves to config.
 - `/status`, `/sethome`, `/update`, `/approve`, and `/deny` are **messaging-only** commands.
 - `/background`, `/voice`, `/reload-mcp`, and `/rollback` work in **both** the CLI and the messaging gateway.
 - `/voice join`, `/voice channel`, and `/voice leave` are only meaningful on Discord.