docs(turn-loop): fix stale plugin defaults + dashboardLinks reader

Verified against nix/agent-modules/claude-settings.nix (claudeMarketplaces
and claudePlugins defaults both gained a second entry — the hive's own
claude-plugins marketplace and base@hyperhive plugin — that the doc never
picked up) and hive-agent/src/web_ui/state.rs (dashboardLinks is read by
the harness's own per-agent web UI, not hive-c0re / the operator
dashboard).

docs/turn-loop/config.md

@@ -71,9 +71,9 @@ hyperhive.dashboardLinks = [
 ];
 ```
 
-Declares extra navigation links that appear on the agent's dashboard
-card and in the per-agent page header alongside the built-in forge /
-config / container links. Each entry has:
+Declares extra navigation links that appear in the per-agent page
+header alongside the built-in forge / config / container links. Each
+entry has:
 
 | Field | Required | Description |
 |-------|----------|-------------|
@@ -82,10 +82,12 @@ config / container links. Each entry has:
 | `icon` | no | Emoji or short glyph prefix. Defaults to empty string. |
 
 The list is written to `<state>/hyperhive-dashboard-links.json` by a
-one-shot systemd unit at container boot. `hive-c0re` reads the file on
-each container-view snapshot and attaches the links to the agent card
-(`kind = External`) without any code change. Omitting the option
-(default empty) produces no extra links.
+one-shot systemd unit at container boot. The harness's own web UI
+(`agent_links` in `hive-agent/src/web_ui/state.rs`) reads the file on
+each `/api/state` snapshot and appends the entries to the per-agent
+nav as `kind = External` links — no `hive-c0re` / operator-dashboard
+involvement, and no code change needed to pick up a new entry.
+Omitting the option (default empty) produces no extra links.
 
 ## Custom static files
 
@@ -174,31 +176,43 @@ hive.
 ## Claude Code plugins
 
 The harness installs Claude Code plugins before the serve loop opens.
-Two per-agent `agent.nix` options control this:
+Three per-agent `agent.nix` options control this:
 
 ```nix
-hyperhive.claudeMarketplaces = [ "anthropics/claude-plugins-official" ];  # default
-hyperhive.claudePlugins = [ "skill-creator@claude-plugins-official" ];     # default
-hyperhive.claudePluginsAutoUpdate = false;                                 # default
+hyperhive.claudeMarketplaces = [                        # default
+  "anthropics/claude-plugins-official"
+  "${hyperhive.packages.claude-plugins}"                # hive's own local marketplace, registered as `hyperhive`
+];
+hyperhive.claudePlugins = [                              # default
+  "skill-creator@claude-plugins-official"
+  "base@hyperhive"
+];
+hyperhive.claudePluginsAutoUpdate = false;               # default
 ```
 
 - **`claudeMarketplaces`** — list of marketplace sources passed to
-  `claude plugin marketplace add <source>`. The official Anthropic
-  marketplace is pre-configured by default; override or extend to add
-  custom marketplaces. Idempotent — re-adding an existing source is
-  a no-op.
+  `claude plugin marketplace add <source>`. Defaults to Anthropic's
+  official marketplace plus hyperhive's own `claude-plugins` nix
+  package (see `nix/packages/claude-plugins.nix`) — a local-path
+  marketplace registered under the name `hyperhive`, so a hive-authored
+  skill needs no forge repo or git remote to ship. Override or extend
+  to add custom marketplaces. Idempotent — re-adding an existing
+  source is a no-op.
 - **`claudePlugins`** — list of plugin specs passed to
   `claude plugin install <spec>`. Each spec is installed on every boot
   (`install` is expected to be idempotent); failures log a warning but
-  do not abort boot. Defaults to Anthropic's `skill-creator`, so every
-  agent can author, refine, and evaluate its own skills without any
-  per-agent wiring.
+  do not abort boot. Defaults to Anthropic's `skill-creator` (so every
+  agent can author, refine, and evaluate its own skills) plus
+  hyperhive's own `base` plugin — skills that apply to every agent
+  regardless of role (currently just `state-hygiene`) — all without
+  any per-agent wiring.
 
 > Both plugin lists follow ordinary NixOS list-option semantics: a
 > per-agent definition **replaces** the default, it does not extend it.
-> An agent that sets `claudePlugins` and still wants `skill-creator`
-> has to list it explicitly alongside its own entries — likewise for
-> the official marketplace in `claudeMarketplaces`.
+> An agent that sets `claudePlugins` and still wants the defaults has
+> to list `skill-creator@claude-plugins-official` and `base@hyperhive`
+> explicitly alongside its own entries — likewise for the two default
+> entries in `claudeMarketplaces`.
 - **`claudePluginsAutoUpdate`** — when `true`, runs
   `claude plugin marketplace update` before installing plugins to pull
   the latest index. Disabled by default to keep boot times short and