chore: scaffold tools/ package + stdlib http client

Per sub-project-2 plan Task 1. Adds tools/ to setuptools packages,
gitignores media/, and a minimal injectable urllib HTTP client.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tools/http.py

@@ -0,0 +1,33 @@
+"""Minimal HTTP client over urllib: timeout, small retry, user-agent. Injectable."""
+
+from __future__ import annotations
+
+import json as _json
+import time
+import urllib.request
+
+USER_AGENT = "human-experience-filter-ingest/0.1 (+local art installation)"
+
+
+class HttpClient:
+    def __init__(self, *, timeout=30.0, retries=2, opener=None):
+        self.timeout, self.retries = timeout, retries
+        self._opener = opener or urllib.request.urlopen
+
+    def get_bytes(self, url, *, headers=None):
+        last = None
+        for attempt in range(self.retries + 1):
+            try:
+                req = urllib.request.Request(
+                    url, headers={"User-Agent": USER_AGENT, **(headers or {})}
+                )
+                with self._opener(req, timeout=self.timeout) as resp:
+                    return resp.read()
+            except Exception as exc:  # noqa: BLE001 - retried below
+                last = exc
+                if attempt < self.retries:
+                    time.sleep(0.2 * (attempt + 1))
+        raise last
+
+    def get_json(self, url, *, headers=None):
+        return _json.loads(self.get_bytes(url, headers=headers).decode("utf-8"))