docs: comprehensive 2-week sweep of feature/PR coverage gaps (#28497)

Catch the website docs up to two weeks of merged work (May 4 – May 18, 2026,
roughly 1,080 PRs). The audit found ~50 user-visible features that had landed
in code with no docs footprint, plus a handful of stale pages. This PR closes
every gap the scan turned up.

New pages
- user-guide/features/deliverable-mode.md — extension list, agent triggers,
  kanban_complete artifacts pattern, [[as_document]] override (PR #27813).
- developer-guide/web-search-provider-plugin.md — authoring guide modeled on
  image-gen-provider-plugin, covering brave_free / ddgs / etc. (PR #25448).

Providers / auth
- Rename "Alibaba Cloud" → "Qwen Cloud (Alibaba DashScope)" everywhere the
  display label shows up; provider id stays `alibaba` (PR #24835).
- Document OAuth refresh-token quarantine for xAI / MiniMax / Codex (PRs
  #28116 / #28118 / #28119).
- Document Nous JWT minting from refresh token + invalid-refresh quarantine
  + cross-profile shared token store (PRs #27663 / #19712).
- Add `## Microsoft Entra ID authentication (keyless)` section to
  azure-foundry guide — DefaultAzureCredential, RBAC, OpenAI + Anthropic
  routing details (PR #28101 / #9df9816da).
- Custom providers `api_mode` is now prompted-and-persisted, not just URL
  autodetected (PR #25068).
- Delegation honours `api_mode` + auto-detects anthropic_messages base URLs
  (PR #26824).
- `x_search` auto-enables when xAI credentials are present (PR #27376).
- Add `xAI Grok OAuth (SuperGrok)` row to providers headline table (PR
  #26534).
- NVIDIA NIM billing-origin header is set automatically (PR #26585).

Windows / installer
- `install.ps1`: document `-Commit <sha>` and `-Tag <v>` pin params plus
  the BOM-strip / git-retry hardening (PR #28169).
- Document Hermes Desktop thin installer + first-launch bootstrap (PR
  #27822).
- Document `dep_ensure` Windows bootstrap (PR #27845).
- Document install-method auto-detection (pip / git / homebrew / nixos) and
  the matching update command (PR #27843).

Gateway / messaging
- `/platform list|pause|resume` full description + circuit-breaker
  semantics (PR #26600).
- Slack / Matrix / Mattermost get parallel `allowed_channels` /
  `allowed_rooms` allowlist sections matching Telegram/Discord/DingTalk
  (PR #21251).
- Discord `allow_any_attachment` + `max_attachment_bytes` (config and env
  vars) (PR #27245).
- Discord clarify-choice button rendering (PR #25485).
- Telegram `guest_mode` @mention bypass for allowlisted groups (PR
  #22759).
- Telegram `notifications` mode (`important` vs `all`) (PR #22793).
- `[[as_document]]` skill / response directive for forcing
  document-style media delivery (PR #21210).

CLI / TUI
- `/new [name]` argument (PR #19637).
- `/subgoal` user-supplied criteria appended to `/goal` (PR #25449).
- `/exit --delete` flag confirmation prompts for destructive slash
  commands (PR #22687).
- Status-bar additions: ▶ N background indicator (PR #27175), context
  compression count (PR #21218), YOLO mode banner+statusbar warning (PR
  #26238).
- `display.timestamps` + `docker_extra_args` config keys (PR #23599).
- TUI collapsible startup banner sections (PR #20625).
- `HERMES_SESSION_ID` exported to tool subprocesses (PR #23847).

i18n
- Refresh display.language locale list from 8 → 16 (en, zh, zh-hant, ja,
  de, es, fr, tr, uk, af, ko, it, ga, pt, ru, hu) — matches
  `agent/i18n.py:SUPPORTED_LANGUAGES`.

Tools / features
- `vision_analyze` native-pixel passthrough for vision-capable callers,
  with auxiliary text-describer fallback (PR #22955).
- `session_search` rewrite to the single-shape tool (discovery / scroll /
  browse modes) (PRs #27590 / #27840).
- Clarify MCP transport scope: client supports stdio + SSE; embedded
  `hermes mcp serve` is stdio-only (PR #21227).
- Web search backends table: add Brave Search (free tier) and DDGS rows
  (PR #21337).
- ACP session-scoped edit auto-approval modes (PR #27862).
- Curator rename map in the user-visible per-run summary (PR #22910).
- Prompt caching feature page reference in features/overview.md — Claude
  cross-session 1-hour prefix cache on native Anthropic / OpenRouter /
  Nous Portal (PR #23828).
- Cron per-job profile parameter (PR #28124).
- `--no-skills` flag for `hermes profile create` (PR #20986).

Build
- Verified with `npm run build` in `website/`; both `en` and `zh-Hans`
  locales compile. Remaining broken-link/anchor warnings are pre-existing
  (`rl-training.md` from learning-path / overview; the
  zh-Hans translation lag the docs skill already calls out).

website/docs/user-guide/security.md

@@ -73,6 +73,8 @@ When YOLO is active, Hermes shows two persistent visual reminders so it's hard t
 YOLO mode disables **all** dangerous command safety checks for the session — **except** the hardline blocklist (see below). Use only when you fully trust the commands being generated (e.g., well-tested automation scripts in disposable environments).
 :::
 
+For destructive session slash commands (`/clear`, `/new` / `/reset`, `/undo`, `/exit --delete`), the CLI also prompts for confirmation before running them. See [Slash Commands — Confirmation prompts for destructive commands](../reference/slash-commands.md#confirmation-prompts-for-destructive-commands).
+
 ### Hardline Blocklist (Always-On Floor)
 
 Some commands are so catastrophic — irreversible filesystem wipes, fork bombs, direct block-device writes — that Hermes refuses to run them **regardless** of:
@@ -605,3 +607,58 @@ TERMINAL_SSH_KEY=~/.ssh/hermes_agent_key
 ```
 
 The SSH connection details live in `.env` (not `config.yaml`) so they aren't checked in or shared along with profile exports. This keeps the gateway's messaging connections separate from the agent's command execution.
+
+## Supply-chain advisory checking
+
+Hermes ships with a built-in advisory scanner that flags Python packages in the active venv that match a curated catalog of known-compromised versions (supply-chain worms like the May 2026 `mistralai 2.4.6` poisoning). Implementation lives in `hermes_cli/security_advisories.py`.
+
+How it runs:
+
+- **CLI startup banner.** A one-line warning is printed if any advisory matches, with a pointer to `hermes doctor` for the full remediation.
+- **`hermes doctor`.** Surfaces every active advisory with version specifics and 2-4 step remediation instructions.
+- **Gateway startup.** Logged to `gateway.log`; the first interactive message gets a short operator banner.
+
+Each advisory carries a stable id. Once you have read and acted on it you can dismiss it for good:
+
+```bash
+hermes doctor --ack <advisory-id>
+```
+
+The ack is persisted to `config.security.acked_advisories` and survives restart. Old advisories are intentionally **not** removed from the catalog — leaving them in place keeps fresh installs warned about historically poisoned versions that might still be cached in a private mirror.
+
+The check itself is stdlib-only and runs from one `importlib.metadata.version()` lookup per advisory, so it's safe to run on every startup.
+
+### Lazy install of optional dependencies
+
+Many features (Mistral TTS, ElevenLabs, Honcho memory, Bedrock, Slack, Matrix, …) depend on Python packages that not every user needs. Hermes installs these **lazily** on first use rather than eagerly under `hermes-agent[all]`. The implementation lives in `tools/lazy_deps.py`.
+
+The trade-off this fixes:
+
+- **Fragility.** When one extra's transitive dependency becomes unavailable on PyPI (quarantined for malware, yanked, broken upload), the entire `[all]` resolve would fail and fresh installs would silently fall back to a stripped tier — losing 10+ unrelated extras at once. Lazy install isolates each backend so one poisoned dep can't break unrelated features.
+- **Bloat.** A user who only ever talks to one provider no longer pulls hundreds of packages they will never import.
+
+How it works:
+
+1. A backend module calls `ensure("feature.name")` at the top of its first-import path.
+2. If the deps are missing, `ensure` checks `security.allow_lazy_installs` in `config.yaml` (default `true`) and runs a venv-scoped `pip install` for the allowlisted specs.
+3. If the install fails or the user has disabled lazy installs, the call raises `FeatureUnavailable` with the actual pip stderr and a pointer at `hermes tools`.
+
+Security guarantees enforced by `tools/lazy_deps.py`:
+
+| Guarantee | What it means |
+|---|---|
+| Venv-scoped only | Installs target `sys.executable` in the active venv — never the system Python |
+| PyPI by name only | Specs accept `"package>=1.0,<2"` syntax. No `--index-url`, `git+https://`, or file: paths — a malicious `config.yaml` cannot redirect the install |
+| Allowlist | Only specs that appear in the in-tree `LAZY_DEPS` map can be installed via this path. A typo in a feature name does NOT get install-anything semantics |
+| Opt-out | Set `security.allow_lazy_installs: false` to disable runtime installs entirely. Useful for restricted networks or strict security postures |
+| No silent retries | Failures surface as `FeatureUnavailable` — no caching of bad state, no retry storms |
+
+To disable runtime installs:
+
+```yaml
+# ~/.hermes/config.yaml
+security:
+  allow_lazy_installs: false
+```
+
+When disabled, backends that need optional deps will tell the user to run the install manually (`pip install …`) or pick a different backend via `hermes tools`.