docs: correctness audit — fix wrong values, add missing coverage (#11972)

Comprehensive audit of every reference/messaging/feature doc page against the
live code registries (PROVIDER_REGISTRY, OPTIONAL_ENV_VARS, COMMAND_REGISTRY,
TOOLSETS, tool registry, on-disk skills). Every fix was verified against code
before writing.

### Wrong values fixed (users would paste-and-fail)

- reference/environment-variables.md:
  - DASHSCOPE_BASE_URL default was `coding-intl.dashscope.aliyuncs.com/v1` \u2192
    actual `dashscope-intl.aliyuncs.com/compatible-mode/v1`.
  - MINIMAX_BASE_URL and MINIMAX_CN_BASE_URL defaults were `/v1` \u2192 actual
    `/anthropic` (Hermes calls MiniMax via its Anthropic Messages endpoint).
- reference/toolsets-reference.md MCP example used the non-existent nested
  `mcp: servers:` key \u2192 real key is the flat `mcp_servers:`.
- reference/skills-catalog.md listed ~20 bundled skills that no longer exist
  on disk (all moved to `optional-skills/`). Regenerated the whole bundled
  section from `skills/**/SKILL.md` \u2014 79 skills, accurate paths and names.
- messaging/slack.md ":::info" callout claimed Slack has no
  `free_response_channels` equivalent; both the env var and the yaml key are
  in fact read.
- messaging/qqbot.md documented `QQ_MARKDOWN_SUPPORT` as an env var, but the
  adapter only reads `extra.markdown_support` from config.yaml. Removed the
  env var row and noted config-only nature.
- messaging/qqbot.md `hermes setup gateway` \u2192 `hermes gateway setup`.

### Missing coverage added

- Providers: AWS Bedrock and Qwen Portal (qwen-oauth) \u2014 both in
  PROVIDER_REGISTRY but undocumented everywhere. Added sections to
  integrations/providers.md, rows to quickstart.md and fallback-providers.md.
- integrations/providers.md "Fallback Model" provider list now includes
  gemini, google-gemini-cli, qwen-oauth, xai, nvidia, ollama-cloud, bedrock.
- reference/cli-commands.md `--provider` enum and HERMES_INFERENCE_PROVIDER
  enum in env-vars now include the same set.
- reference/slash-commands.md: added `/agents` (alias `/tasks`) and `/copy`.
  Removed duplicate rows for `/snapshot`, `/fast` (\u00d72), `/debug`.
- reference/tools-reference.md: fixed "47 built-in tools" \u2192 52. Added
  `feishu_doc` and `feishu_drive` toolset sections.
- reference/toolsets-reference.md: added `feishu_doc` / `feishu_drive` core
  rows + all missing `hermes-<platform>` toolsets in the platform table
  (bluebubbles, dingtalk, feishu, qqbot, wecom, wecom-callback, weixin,
  homeassistant, webhook, gateway). Fixed the `debugging` composite to
  describe the actual `includes=[...]` mechanism.
- reference/optional-skills-catalog.md: added `fitness-nutrition`.
- reference/environment-variables.md: added NOUS_BASE_URL,
  NOUS_INFERENCE_BASE_URL, NVIDIA_API_KEY/BASE_URL, OLLAMA_API_KEY/BASE_URL,
  XAI_API_KEY/BASE_URL, MISTRAL_API_KEY, AWS_REGION/AWS_PROFILE,
  BEDROCK_BASE_URL, HERMES_QWEN_BASE_URL, DISCORD_ALLOWED_CHANNELS,
  DISCORD_PROXY, TELEGRAM_REPLY_TO_MODE, MATRIX_DEVICE_ID, MATRIX_REACTIONS,
  QQBOT_HOME_CHANNEL_NAME, QQ_SANDBOX.
- messaging/discord.md: documented DISCORD_ALLOWED_CHANNELS, DISCORD_PROXY,
  HERMES_DISCORD_TEXT_BATCH_DELAY_SECONDS and HERMES_DISCORD_TEXT_BATCH_SPLIT
  _DELAY_SECONDS (all actively read by the adapter).
- messaging/matrix.md: documented MATRIX_REACTIONS (default true).
- messaging/telegram.md: removed the redundant second Webhook Mode section
  that invented a `telegram.webhook_mode: true` yaml key the adapter does
  not read.
- user-guide/features/hooks.md: added `on_session_finalize` and
  `on_session_reset` (both emitted via invoke_hook but undocumented).
- user-guide/features/api-server.md: documented GET /health/detailed, the
  `/api/jobs/*` CRUD surface, POST /v1/runs, and GET /v1/runs/{id}/events
  (10 routes that were live but undocumented).
- user-guide/features/fallback-providers.md: added `approval` and
  `title_generation` auxiliary-task rows; added gemini, bedrock, qwen-oauth
  to the supported-providers table.
- user-guide/features/tts.md: "seven providers" \u2192 "eight" (post-xAI add
  oversight in #11942).
- user-guide/configuration.md: TTS provider enum gains `xai` and `gemini`;
  yaml example block gains `mistral:`, `gemini:`, `xai:` subsections.
  Auxiliary-provider enum now enumerates all real registry entries.
- reference/faq.md: stale AIAgent/config examples bumped from
  `nous/hermes-3-llama-3.1-70b` and `claude-sonnet-4.6` to
  `claude-opus-4.7`.

### Docs-site integrity

- guides/build-a-hermes-plugin.md referenced two nonexistent hooks
  (`pre_api_request`, `post_api_request`). Replaced with the real
  `on_session_finalize` / `on_session_reset` entries.
- messaging/open-webui.md and features/api-server.md had pre-existing
  broken links to `/docs/user-guide/features/profiles` (actual path is
  `/docs/user-guide/profiles`). Fixed.
- reference/skills-catalog.md had one `<1%` literal that MDX parsed as a
  JSX tag. Escaped to `&lt;1%`.

### False positives filtered out (not changed, verified correct)

- `/set-home` is a registered alias of `/sethome` \u2014 docs were fine.
- `hermes setup gateway` is valid syntax (`hermes setup \<section\>`);
  changed in qqbot.md for cross-doc consistency, not as a bug fix.
- Telegram reactions "disabled by default" matches code (default `"false"`).
- Matrix encryption "opt-in" matches code (empty env default \u2192 disabled).
- `pre_api_request` / `post_api_request` hooks do NOT exist in current code;
  documented instead the real `on_session_finalize` / `on_session_reset`.
- SIGNAL_IGNORE_STORIES is already in env-vars.md (subagent missed it).

Validation:
- `docusaurus build` \u2014 passes (only pre-existing nix-setup anchor warning).
- `ascii-guard lint docs` \u2014 124 files, 0 errors.
- 22 files changed, +317 / \u2212158.

website/docs/user-guide/features/tts.md

@@ -14,7 +14,7 @@ If you have a paid [Nous Portal](https://portal.nousresearch.com) subscription,
 
 ## Text-to-Speech
 
-Convert text to speech with seven providers:
+Convert text to speech with eight providers:
 
 | Provider | Quality | Cost | API Key |
 |----------|---------|------|---------|