assistant: teach the agent about Search admin

Bring the LLM agent's prompts and tools current with the new /search
section and arcadia-search admin sidecar:

- New tools in admin-tools.ts:
  - list_search_corpora: enumerate tenants + corpora with build status,
    so the agent can pick a real corpus instead of guessing.
  - rebuild_search_corpus(tenant, corpus): isWrite=true, surfaces a
    confirm card. Use after uploads or when results look stale.
- search_kb description updated: names docs / operator-tools / files
  explicitly, and points at list_search_corpora when unsure.
- ARCADIA_KNOWLEDGE: adds search-corpus terminology, /search route,
  and a one-liner pointer to the three new tools.
- assistant.tsx UI_CONTROL_PREFACE: nav-search added, full Search
  page action catalog (search-refresh / -restart / -new-tenant /
  -new-corpus, corpora-search, per-row corpus-{t}-{c}-{rebuild,edit,
  delete,actions}, tenant-{id}-delete, dialog form fields). Recipe
  for the manual rebuild path, plus a note steering the agent to
  the rebuild_search_corpus tool by default.
- search.tsx publishes a "search" surface to admin-context with
  tenants + corpora summary, so the agent gets live state without
  needing a tool call when /search is mounted.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/lib/admin-tools.ts

@@ -30,6 +30,7 @@ import { listRoles } from "~/lib/arcadia/roles"
 import { revokeUserApiKey } from "~/lib/arcadia/api-keys"
 import { createRAGClient } from "@crema/lexical-rag-ui"
 import { BLOCK_INDEX, getBlockSchema } from "~/lib/block-schemas"
+import { searchAdmin, SearchAdminError } from "~/lib/search-admin"
 
 // Lazy singleton — first tool call fetches /docs-index.json, subsequent
 // calls reuse the parsed MiniSearch instance.
@@ -732,7 +733,7 @@ const TOOLS: ToolDef[] = [
   {
     name: "search_kb",
     description:
-      "Lexical (BM25) search over the arcadia-search Tantivy backend. Use for the LARGER, server-hosted knowledge corpora — the same arcadia docs the browser RAG serves are indexed here as `corpus=docs` for parity, and additional corpora (uploaded files, runbooks, etc.) will land here as they're added. Returns chunks with snippets + chunk_ids that can be passed to `read_chunk` to expand. Prefer this over `search_docs` (browser) when you need richer hits or when the user is asking about content that wouldn't be in the bundled docs (e.g. uploaded files).",
+      "Lexical (BM25) search over the arcadia-search Tantivy backend. Returns chunks with snippets + chunk_ids that can be passed to `read_chunk` to expand. Prefer this over `search_docs` (browser) when you need richer hits or when the content wouldn't be in the bundled docs.\n\nKnown corpora on the platform-admin tenant:\n- `docs` — arcadia-app architecture/ops docs (same as the browser RAG, server-hosted for parity).\n- `operator-tools` — arcadia-search + arcadia-admin documentation (admin sidecar, deploy script, search admin UI, MULTI_TENANT, RAG, AI_FIRST, LIBS, LLM_PROXY_CONTRACT).\n- `files` — markdown/text files uploaded by tenant users via arcadia-app.\n\nIf you're not sure what's available, call `list_search_corpora` first. Operators can add new corpora via the `/search` route.",
     parameters: {
       type: "object",
       properties: {
@@ -740,7 +741,7 @@ const TOOLS: ToolDef[] = [
         corpus: {
           type: "string",
           description:
-            "Which indexed corpus to search. `docs` is the parity corpus (arcadia documentation). New corpora are added by the operator.",
+            "Which indexed corpus to search. See list_search_corpora for the live set; common values: `docs`, `operator-tools`, `files`.",
         },
         limit: {
           type: "integer",
@@ -796,6 +797,84 @@ const TOOLS: ToolDef[] = [
       return result
     },
   },
+  {
+    name: "list_search_corpora",
+    description:
+      "Enumerate the corpora currently configured on the arcadia-search admin sidecar. Returns each tenant's corpora with build status (indexed?, num_docs). Call this when you don't know what corpora exist before invoking `search_kb`, or when the user asks what knowledge is available. Requires the search admin token to be configured.",
+    parameters: {
+      type: "object",
+      properties: {},
+      additionalProperties: false,
+    },
+    isWrite: false,
+    run: async () => {
+      try {
+        const tenantsRes = await searchAdmin.listTenants()
+        const tenants = await Promise.all(
+          tenantsRes.tenants.map(async (t) => {
+            try {
+              const c = await searchAdmin.listCorpora(t.id)
+              return {
+                tenant: t.id,
+                corpora: c.corpora.map((cc) => ({
+                  corpus: cc.corpus,
+                  indexed: cc.indexed,
+                  num_docs: cc.num_docs,
+                })),
+              }
+            } catch {
+              return { tenant: t.id, corpora: [] }
+            }
+          }),
+        )
+        return { tenants }
+      } catch (err) {
+        if (err instanceof SearchAdminError) {
+          return {
+            error: `search-admin ${err.status}: ${err.message}`,
+            hint: "VITE_ARCADIA_SEARCH_ADMIN_TOKEN may be unset, or the sidecar (default :7801) may be down.",
+          }
+        }
+        throw err
+      }
+    },
+  },
+  {
+    name: "rebuild_search_corpus",
+    description:
+      "Trigger a synchronous rebuild of one corpus on arcadia-search. Use when the operator says the index is stale, after they've uploaded new files, or when search_kb returned suspiciously few/old hits. Returns chunk_count and built_at on success. The operator confirms before the rebuild runs (rebuilds can take seconds–minutes depending on corpus size).",
+    parameters: {
+      type: "object",
+      properties: {
+        tenant: {
+          type: "string",
+          description: "Search tenant id (e.g. `platform-admin`). See list_search_corpora for available tenants.",
+        },
+        corpus: {
+          type: "string",
+          description: "Corpus name within that tenant (e.g. `docs`, `operator-tools`, `files`).",
+        },
+      },
+      required: ["tenant", "corpus"],
+      additionalProperties: false,
+    },
+    isWrite: true,
+    run: async (args) => {
+      const tenant = typeof args.tenant === "string" ? args.tenant.trim() : ""
+      const corpus = typeof args.corpus === "string" ? args.corpus.trim() : ""
+      if (!tenant || !corpus) {
+        throw new Error("rebuild_search_corpus requires { tenant, corpus }")
+      }
+      try {
+        return await searchAdmin.rebuild(tenant, corpus)
+      } catch (err) {
+        if (err instanceof SearchAdminError) {
+          return { error: `search-admin ${err.status}: ${err.message}` }
+        }
+        throw err
+      }
+    },
+  },
   {
     name: "get_block_schema",
     description: `Fetch the full JSON schema + example for a rich-output block kind so you can emit it correctly in your reply. Call this the first time in a thread that you intend to render a particular kind. Available kinds: ${Object.entries(