feat(screenshots): real netOrk screenshots from an anonymized demo copy

The site has shown hand-built JSX mockups of the UI so far. This adds the
tooling to replace them with screenshots of the real application:

- scripts/demo/up.sh restores a pg_dump of a production database into a
  local Postgres and starts netOrk (a pinned release, default v0.28.0) with
  only the API and the UI: no worker, no beat, no Redis, a random encryption
  key. Nothing polls and nothing can reach a device.
- scripts/demo/anonymize.py rewrites every text, JSON and address column of
  every table: domains to example.demo, private IPv4 per /16 with the host
  part kept, public addresses into the documentation ranges, MACs with the
  vendor prefix kept, e-mail addresses and configured names. Secrets are
  emptied by column name, one admin "netork" is left. It refuses non-local
  databases and ends with a leak report. The real-to-demo name map lives
  outside the repo.
- scripts/screenshots/capture.py drives headless Chromium through a
  declarative list of pages, logs in to the demo copy by itself, and aborts
  every non-GET API request, so taking screenshots cannot change anything.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/screenshots/shots.py

@@ -0,0 +1,37 @@
+"""The screenshots the website uses, as data.
+
+Each shot is one page of the netOrk UI. `path` may contain `{placeholders}`
+that are filled from `--var name=value` on the command line (device IDs
+differ per instance, so they are never hard-coded here). Device detail
+sections are addressed through the URL hash the UI itself writes
+(`#security/assessment`, `#config`, ...), so no clicking is needed.
+
+`mask` lists extra CSS selectors to cover on top of the automatic masks
+(public IPv4 addresses, e-mail addresses, and the terms from the mask file).
+"""
+
+from dataclasses import dataclass, field
+
+
+@dataclass
+class Shot:
+    name: str
+    path: str
+    # Selector that must be visible before the shot is taken.
+    wait_for: str = "main"
+    mask: list[str] = field(default_factory=list)
+    full_page: bool = False
+    # Crop height in CSS pixels; None keeps the viewport height.
+    height: int | None = None
+
+
+SHOTS: list[Shot] = [
+    Shot("devices", "/devices"),
+    Shot("device-detail", "/devices/{ap}#networking/interfaces"),
+    Shot("vlans", "/vlans"),
+    Shot("device-security", "/devices/{server}#security/assessment"),
+    Shot("vulnerabilities", "/vulnerabilities"),
+    Shot("dashboard", "/"),
+    Shot("audit-log", "/audit-log"),
+    Shot("service-checks", "/monitoring/checks"),
+]