Save in-progress keysat integration and StartOS 0.4 work

Snapshot of the working tree before cleanup. Captures:
- Keysat licensing: server/license.js, /api/license/* endpoints in
  server/index.js, activation modal in public/index.html, embedded
  Ed25519 issuer key (assets/issuer.pub).
- StartOS 0.4 expansion: setApiKey action, version files v0.1.1
  through v0.1.15, file-models/config.json.ts, manifest updates.
- Self-hosted registry server (startos-registry/).
- Build/deploy scripts (bin/bump-version.sh, bin/deploy.sh, vendored
  yt-dlp binary), .gitignore, .deploy.env.example.
- Recent design docs (KEYSAT_INTEGRATION.md, UPGRADE-DESIGN.md) —
  retained here so they remain recoverable when removed in the
  follow-up cleanup commit.

startos-registry/node_modules/inherits/inherits_browser.js

@@ -0,0 +1,27 @@
+if (typeof Object.create === 'function') {
+  // implementation from standard node.js 'util' module
+  module.exports = function inherits(ctor, superCtor) {
+    if (superCtor) {
+      ctor.super_ = superCtor
+      ctor.prototype = Object.create(superCtor.prototype, {
+        constructor: {
+          value: ctor,
+          enumerable: false,
+          writable: true,
+          configurable: true
+        }
+      })
+    }
+  };
+} else {
+  // old school shim for old browsers
+  module.exports = function inherits(ctor, superCtor) {
+    if (superCtor) {
+      ctor.super_ = superCtor
+      var TempCtor = function () {}
+      TempCtor.prototype = superCtor.prototype
+      ctor.prototype = new TempCtor()
+      ctor.prototype.constructor = ctor
+    }
+  }
+}