docs(readmes): address audit

frontend/README.md:
- swarm-ui has real pages (HivesPage, AgentsPage, JobsPage,
  CreateAgentForm, IssueReportPage, account-linking forms, routed in
  App.tsx) and is served via nix/host-modules/swarm-ui.nix +
  swarm-controller's swarm-ui-facing endpoints — drop the stale
  package.json-derived 'no functionality yet' claim
- dashboard is a vanilla-JS + custom-element MPA (core.js, common.js,
  tabs.js, ...) with a couple of Preact-rendered pages (builds.js,
  swarm.js), not uniformly Preact like agent/swarm-ui
- drop the build.mjs line-count guess (actual: agent=93,
  dashboard=134, swarm-ui=167)

frontend/README.md

@@ -7,8 +7,8 @@ npm workspaces project for the hyperhive browser-facing assets:
 - `packages/dashboard/` — the hive-c0re dashboard SPA.
 - `packages/agent/` — the per-container web UI (default agent page,
   stats, screen).
-- `packages/swarm-ui/` — the swarm-level operator UI shell (project-
+- `packages/swarm-ui/` — the swarm-level operator UI shell (hives,
-  bootstrap scope, no functionality yet).
+  agents, jobs, issue-report pages).
 
 ## Build
 
@@ -28,9 +28,11 @@ layers per-agent additions on top of the default agent dist.
 - **Hermetic**: dependencies vendored via the checked-in lockfile;
   `buildNpmPackage` in nix uses it as the source-of-truth so the
   output is reproducible without network access at build time.
-- **esbuild**: each package is a small Preact app, bundled with no
+- **esbuild**: `agent` and `swarm-ui` are Preact apps; `dashboard` is a
-  framework beyond Preact itself. Each workspace's `build.mjs` is ~30
+  vanilla-JS + custom-element MPA with a few Preact-rendered pages
-  lines.
+  (`builds.js`, `swarm.js`); `shared` holds both kinds of module. No
+  framework runtime beyond Preact where it's used. Each workspace's
+  `build.mjs` is a short esbuild script.
 - **Single-PR migration**: see the tracked design proposal and
   the four-commit shape (npm scaffold → nix derivations → container
   plumbing → Rust cutover).