feat(gateway): unify QQBot branding, add PLATFORM_HINTS, fix streaming, restore missing setup functions

- Rename platform from 'qq' to 'qqbot' across all integration points
  (Platform enum, toolset, config keys, import paths, file rename qq.py → qqbot.py)
- Add PLATFORM_HINTS for QQBot in prompt_builder (QQ supports markdown)
- Set SUPPORTS_MESSAGE_EDITING = False to skip streaming on QQ
  (prevents duplicate messages from non-editable partial + final sends)
- Add _send_qqbot() standalone send function for cron/send_message tool
- Add interactive _setup_qq() wizard in hermes_cli/setup.py
- Restore missing _setup_signal/email/sms/dingtalk/feishu/wecom/wecom_callback
  functions that were lost during the original merge

cli-config.yaml.example

@@ -523,7 +523,7 @@ agent:
 #   - A preset like "hermes-cli" or "hermes-telegram" (curated tool set)
 #   - A list of individual toolsets to compose your own (see list below)
 #
-# Supported platform keys: cli, telegram, discord, whatsapp, slack
+# Supported platform keys: cli, telegram, discord, whatsapp, slack, qqbot
 #
 # Examples:
 #
@@ -552,7 +552,7 @@ agent:
 #   slack:         hermes-slack          (same as telegram)
 #   signal:        hermes-signal         (same as telegram)
 #   homeassistant: hermes-homeassistant  (same as telegram)
-#   qq:            hermes-qq            (same as telegram)
+#   qqbot:            hermes-qqbot            (same as telegram)
 #
 platform_toolsets:
   cli: [hermes-cli]
@@ -562,7 +562,7 @@ platform_toolsets:
   slack: [hermes-slack]
   signal: [hermes-signal]
   homeassistant: [hermes-homeassistant]
-  qq: [hermes-qq]
+  qqbot: [hermes-qqbot]
 
 # ─────────────────────────────────────────────────────────────────────────────
 # Available toolsets (use these names in platform_toolsets or the toolsets list)