docs(examples): add the CMS proof-of-concept dogfooding artifact

A WordPress-inspired CMS whose entire backend is PiCloud Rhai scripts
deployed with pic apply, plus a SvelteKit frontend. Built to dogfood the
project tool, CLI, and SDK; exercises docs/kv/files/users, docs+queue+cron
+pubsub triggers, the transactional-outbox notification chain, a docs
before-interceptor, set_if CAS, SSE, per-app CORS, env overlays, and a
durable Workflow (validate -> enrich || seo -> publish -> finalize) started
with workflow::start and polled with workflow::run_status, visualized live
with Svelte Flow.

FINDINGS.md / SECURITY.md capture every gap, surprise, and security issue
found (each tagged [PiCloud] vs [CMS]); the platform fixes for the
actionable ones ship in the preceding commit.

Also folds in the read-only `pic` allowlist entries added to
.claude/settings.json during the session (fewer-permission-prompts).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/cms-poc/scripts/posts/post_create.rhai

@@ -0,0 +1,39 @@
+// POST /cms/admin/posts — create a post (author+).
+import "auth" as auth;
+import "util" as util;
+let g = auth::guard(ctx, ["admin", "author"]);
+if !g.ok { return g.response; }
+let user = g.user;
+
+let b = ctx.request.body;
+if b == () || b.title == () {
+    return #{ statusCode: 400, body: #{ error: "title required" } };
+}
+
+let posts = docs::collection("posts");
+let idx = kv::collection("slugs");
+let slug = if b.slug == () { util::slugify(b.title) } else { util::slugify(b.slug) };
+if idx.has("post:" + slug) {
+    slug = slug + "-" + random::string(4).to_lower();
+}
+
+let now = time::now();
+let status = if b.status == () { "draft" } else { b.status };
+let publish_at = ();
+if status == "published" { publish_at = now; }
+else if status == "scheduled" && b.publish_at != () { publish_at = b.publish_at; }
+
+let data = #{
+    title: b.title,
+    slug: slug,
+    body_md: if b.body_md == () { "" } else { b.body_md },
+    excerpt: if b.excerpt == () { "" } else { b.excerpt },
+    status: status,
+    author_id: user.id,
+    author_name: user.display_name,
+    tags: if b.tags == () { [] } else { b.tags },
+    publish_at: publish_at,
+};
+let id = posts.create(data);
+idx.set("post:" + slug, id);
+#{ statusCode: 201, body: #{ id: id, slug: slug, status: status } }