Wire AI assistant to arcadia: domain primer, tool calling, admin context

Make /ai and /assistant operate as the platform admin's assistant
against arcadia-app's API:

- Add `arcadia-knowledge.ts` — domain primer (multi-tenant Phoenix
  backend, tenant lifecycle, platform_admins identity, etc.) baked into
  every system prompt.
- Add `admin-tools.ts` — curated tool registry exposing `list_tenants`
  and `get_tenant`, callable via OpenAI-native function calling. Tools
  hit arcadia through `useArcadiaClient()` and inherit the operator's
  JWT + tenant header. `runLLMToolCalls()` returns `tool` role messages
  ready to push back into history.
- Add `admin-context.ts` — runtime registry pages publish to so the
  assistant can answer factual questions about live UI state without
  scraping the DOM. Tenants page registers its summary on mount.
- Replace generic Vibespace personas (Atlas/Forge/Inkwell/Pilot/Cursor)
  with arcadia-flavoured ones: Operator, Auditor, Triage, Analyst,
  UI Operator. Auto-migrate stored agents from the legacy set.
- /assistant: build admin preface (role + primer + persona + ctx) and
  pass it as the `useChat` system at construction. Pass `tools` on every
  `send()`. Auto-loop reads `toolCalls` off the streaming assistant
  message and uses `continueChat()` to push tool results.
- /ai: same wiring (this is the canonical admin chat surface; the user
  prefers its look).
- MessageBody renders tool-result cards (role: "tool") and a "Called X"
  pill on assistant messages with toolCalls. Strips Qwen-style
  `<tool_call>` XML from prose when the tags were converted to
  structured calls.
- Extend ThreadMessage with the `tool` role + tool-call metadata so
  conversations round-trip through localStorage.
- Tenants page: row actions get `data-action="tenant-<slug>-{suspend,
  activate,deactivate}"` (via lib-table-ui's new dataAction prop);
  registers tenant summary into admin-context.

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

app/lib/admin-context.ts

@@ -0,0 +1,76 @@
+// Shared state surface that any admin page can publish to so the assistant
+// can read live data without scraping the DOM.
+//
+// Pages call `useRegisterAdminContext("tenants", { tenants: [...] })` while
+// mounted; the assistant calls `getAdminContextSnapshot()` each turn to
+// inject a structured snapshot into the system prompt.
+
+import { useEffect } from "react"
+
+type Surface = Record<string, unknown>
+
+export type AdminContextSnapshot = {
+  route: string
+  surfaces: Record<string, Surface>
+}
+
+const surfaces = new Map<string, Surface>()
+
+export function publishAdminSurface(name: string, data: Surface): void {
+  surfaces.set(name, data)
+  if (typeof window !== "undefined") {
+    ;(window as unknown as { __adminContext?: unknown }).__adminContext = getAdminContextSnapshot()
+  }
+}
+
+export function clearAdminSurface(name: string): void {
+  surfaces.delete(name)
+  if (typeof window !== "undefined") {
+    ;(window as unknown as { __adminContext?: unknown }).__adminContext = getAdminContextSnapshot()
+  }
+}
+
+export function getAdminContextSnapshot(): AdminContextSnapshot {
+  const route = typeof window !== "undefined" ? window.location.pathname : ""
+  return {
+    route,
+    surfaces: Object.fromEntries(surfaces.entries()),
+  }
+}
+
+/**
+ * Render a snapshot as a markdown block for the LLM system prompt.
+ * Keeps it compact: route, then one section per surface with JSON.
+ */
+export function formatAdminContextForPrompt(snapshot = getAdminContextSnapshot()): string {
+  const sections: string[] = [`Admin context (read-only — for answering factual questions):`]
+  sections.push(`Route: ${snapshot.route || "?"}`)
+  const names = Object.keys(snapshot.surfaces)
+  if (names.length === 0) {
+    sections.push(`Surfaces: (none registered)`)
+  } else {
+    for (const name of names) {
+      const json = safeJson(snapshot.surfaces[name])
+      sections.push(`Surface "${name}":\n${json}`)
+    }
+  }
+  return sections.join("\n\n")
+}
+
+function safeJson(value: unknown): string {
+  try {
+    const text = JSON.stringify(value, null, 2)
+    if (text.length > 4000) return text.slice(0, 4000) + "\n…(truncated)"
+    return text
+  } catch {
+    return "(unserializable)"
+  }
+}
+
+/** Hook: publish a surface while the component is mounted. */
+export function useRegisterAdminContext(name: string, data: Surface): void {
+  useEffect(() => {
+    publishAdminSurface(name, data)
+    return () => clearAdminSurface(name)
+  }, [name, data])
+}