feat: introduce archify skill for generating architecture diagrams

- Added a new Archify skill, enabling users to create polished architecture, workflow, sequence, data-flow, and lifecycle diagrams.
- Implemented comprehensive functionality including rendering, validation, and delivery of diagrams in various formats.
- Integrated a user-friendly command-line interface for generating and previewing diagrams.
- Developed supporting files including package.json, LICENSE, and SKILL.md for documentation and licensing.
- Added unit tests to ensure reliability and functionality of the new skill.

These changes enhance the application by providing a structured approach to visualizing system architecture and workflows, improving user experience and data representation.

.agents/skills/archify/test/base-input-compatibility.test.mjs

@@ -0,0 +1,42 @@
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import fs from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+import test from 'node:test';
+import { fileURLToPath } from 'node:url';
+
+const here = path.dirname(fileURLToPath(import.meta.url));
+const skillRoot = path.resolve(here, '..');
+const tmp = fs.mkdtempSync(path.join(os.tmpdir(), 'archify-base-input-compatibility-'));
+
+function renderBaseFixture(type, name) {
+  const input = path.join(skillRoot, 'test', 'fixtures', 'v1-baseline', name);
+  const output = path.join(tmp, `${name}.html`);
+  return spawnSync(process.execPath, [
+    path.join(skillRoot, 'bin', 'archify.mjs'),
+    'render',
+    type,
+    input,
+    output,
+  ], {
+    cwd: skillRoot,
+    encoding: 'utf8',
+  });
+}
+
+test('base named-route fixtures remain valid without redundant authored endpoint sides', () => {
+  for (const [type, name] of [
+    ['dataflow', 'event-stream.dataflow.json'],
+    ['architecture', 'production-deployment.architecture.json'],
+  ]) {
+    const result = renderBaseFixture(type, name);
+    assert.equal(
+      result.status,
+      0,
+      `${type} base input must remain valid:\n${result.stdout || result.stderr}`,
+    );
+  }
+});
+
+process.on('exit', () => fs.rmSync(tmp, { recursive: true, force: true }));