feat: add plug-and-play devRant API client examples with Python and JavaScript

Add complete set of example scripts for the devRant REST protocol under
examples/devrant/, including reusable client libraries, a rant poster,
a live feed watcher with keyword-based auto-upvote, and an end-to-end
smoke test that exercises every endpoint. Both Python (stdlib-only) and
JavaScript (Node 18+ global fetch) implementations are provided.

examples/devrant/post_rant.py

@@ -0,0 +1,24 @@
+# retoor <retoor@molodetz.nl>
+
+import sys
+
+from client import from_env
+
+
+def main() -> None:
+    if len(sys.argv) < 2:
+        print("usage: DEVRANT_USERNAME=.. DEVRANT_PASSWORD=.. python post_rant.py <text> [tags]")
+        raise SystemExit(1)
+    text = sys.argv[1]
+    tags = sys.argv[2] if len(sys.argv) > 2 else ""
+    api = from_env()
+    api.login()
+    result = api.post_rant(text, tags)
+    if result.get("success"):
+        print(f"posted rant {result['rant_id']}")
+    else:
+        print(f"failed: {result.get('error')}")
+
+
+if __name__ == "__main__":
+    main()