feat: add /llms.txt route for AI agent discovery

Implements the llms.txt standard (https://llmstxt.org/) to make Frontside's
open source projects discoverable by AI agents.

- Add assets/llms.txt with content describing Frontside services and projects
- Add routes/llms-txt-route.ts that reads and serves the llms.txt file
- Wire route in main.tsx before legacy proxy catch-all
- Upgrade effection from 3.2.0 to 3.6.1

Author: taras

assets/llms.txt

@@ -0,0 +1,34 @@
+# Frontside
+
+> Frontside is a software consultancy specializing in Developer Experience (DX),
+> internal developer platforms, and open source tools for JavaScript.
+
+Frontside helps engineering teams build better developer experiences, from local
+development environments to production deployment pipelines. We specialize in
+Backstage implementation, testing strategy, and structured concurrency.
+
+## Services
+
+- [DX Consulting](https://frontside.com/dx-consulting): Developer experience consulting for Cloud native teams
+- [Backstage Implementation](https://frontside.com/backstage): Internal developer portal expertise and plugin development
+
+## Open Source Projects
+
+- [Effection](https://frontside.com/effection/llms.txt): Structured concurrency for JavaScript - see detailed llms.txt for API docs and extension packages
+- [Interactors](https://frontside.com/interactors): Page objects for component library testing
+- [GraphGen](https://frontside.com/graphgen): Generate realistic graph data for testing
+
+## Blog
+
+Technical articles on DX, testing, Backstage, and JavaScript. Notable posts:
+
+- [Announcing Effection 4.0](https://frontside.com/blog/2025-12-23-announcing-effection-v4): Major release with improved determinism
+- [The Heartbreaking Inadequacy of AbortController](https://frontside.com/blog/2025-08-04-the-heartbreaking-inadequacy-of-abort-controller): Why JavaScript needs structured concurrency
+- [Effection: When async/await is not enough](https://frontside.com/blog/2021-10-26-effection-async-await): Introduction to structured concurrency
+
+## Optional
+
+- [All blog posts](https://frontside.com/blog)
+- [About Frontside](https://frontside.com/about)
+- [Contact](https://frontside.com/contact)
+- [Case Study: Resideo](https://frontside.com/work/case-studies/resideo)

deno.json

@@ -18,7 +18,8 @@
     "jsxImportSource": "revolution"
   },
   "imports": {
-    "effection": "jsr:@effection/effection@3.2.0",
+    "effection": "jsr:@effection/effection@3.6.1",
+    "@effectionx/fs": "npm:@effectionx/fs",
     "hast": "npm:hast@^1.0.0",
     "revolution": "https://deno.land/x/revolution@0.6.1/mod.ts",
     "revolution/jsx-runtime": "https://deno.land/x/revolution@0.6.1/jsx-runtime.ts"

main.tsx

@@ -10,6 +10,7 @@ import { backstageServicesRoute } from "./routes/backstage.html.tsx";
 import { dxConsultingServicesRoute } from "./routes/dx-consulting.html.tsx";
 import { pluginWorkshopRoute } from "./routes/advanced-backstage-plugin-development-route.tsx";
 import { resideoBackstageCaseStudyRoute } from "./routes/work/case-studies/case-study-resideo.html.tsx";
+import { llmsTxtRoute } from "./routes/llms-txt-route.ts";
 
 import { etagPlugin } from "./plugins/etag.ts";
 import { currentRequestPlugin } from "./plugins/current-request.ts";
@@ -31,6 +32,7 @@ await main(function* (args) {
 
   let revolution = createRevolution({
     app: [
+      route("/llms.txt", llmsTxtRoute()),
       route("/", indexRoute()),
       route("/blog", blogIndexRoute()),
       route("/blog/:id", blogPostRoute()),

routes/llms-txt-route.ts

@@ -0,0 +1,22 @@
+import type { HTTPMiddleware } from "revolution";
+import { call } from "effection";
+
+/**
+ * Serves the /llms.txt file for AI agent discovery.
+ *
+ * This follows the llms.txt standard (https://llmstxt.org/) to help
+ * AI agents understand and navigate Frontside's content and projects.
+ */
+export function llmsTxtRoute(): HTTPMiddleware {
+  return function* () {
+    const content = yield* call(() =>
+      Deno.readTextFile(new URL("../assets/llms.txt", import.meta.url))
+    );
+    return new Response(content, {
+      headers: {
+        "Content-Type": "text/plain; charset=utf-8",
+        "Cache-Control": "public, max-age=3600",
+      },
+    });
+  };
+}