lab-ops-hub: container validator still allows DEL/C1-control, NBSP and WHATWG-forbidden (<>^|) hosts the Worker validator refuses #510

Summary

PR #508 (fix for #507) added a whitespace check to the lab-ops-hub container crawler's validate_crawl_url (pkgs/lab-ops-hub/container/app.py:63 on main d4809cff):

if any(ord(c) <= 0x20 for c in host):
    raise ValueError(f"refusing to crawl host with whitespace {host!r}")

Its comment says "A space or control character in the host is not a DNS name", but ord(c) <= 0x20 covers only the C0 controls + space. The remaining control characters and the rest of the WHATWG forbidden-host set still fall through and are certified as "a public DNS name", while the Worker's validateCrawlUrl (pkgs/lab-ops-hub/src/lib.ts:129) refuses every one of them outright:

Controls, identical on both sides (must not change): ordinary DNS names, http://exam_ple.com/, and valid IDN hosts (e.g. examéple.com) are ALLOW/ALLOW — so the fix must not blanket-ban non-ASCII.

Evidence

• PR: fix(lab-ops-hub): container validator refuses space hosts and IPvFuture literals #508, commit ebbeb8bca08895de704c720526b7842235590249, merged as d4809cffa77d9fb4695262445802a197ab1b6b4e.
• Verified on current main d4809cff (git origin/main and gh api agree) by driving both real validators over the same battery: every printable ASCII character plus 0x7F–0xA0, é and a combining char, each embedded as http://exam<char>ple.com/ (TS via bun importing src/lib.ts, Python by importing container/app.py). The complete set of divergences was exactly: <, >, ^, |, 0x7F, 0x80–0x9F, 0xA0.
• The DEL case reproduces lab-ops-hub: container validator accepts space hosts and IPvFuture literals the Worker validator refuses #507's exact lazy-failure shape: Python's own fetcher rejects it deep inside http.client, whose disallowed-character check is [\\x00-\\x20\\x7f] — i.e. http.client.HTTPConnection("exam\\x7fple.com").putrequest(...) raises InvalidURL: URL can't contain control characters — but the validator's new check stops one codepoint short of the fetcher's own set. The < > ^ | hosts are WHATWG forbidden host codepoints; no DNS resolver accepts them either, so those crawls also die below the validator instead of at it.

Why it matters

The container validator is the defence-in-depth re-check on the component that actually fetches (#441), and the parity premise of #468/#502/#505/#507 is that where the two validators disagree, the effective policy is the weaker one. PR #508 closed the space/C0 part of this class but left the validator's stated rule ("space or control character") under-implemented: a whole tail of not-a-DNS-name hosts is still certified as public DNS names, pushing the failure into the fetcher/resolver as a low-level error and leaving the guard's verdict meaningless for them.

Cross-repo note: this validator pair lives only in developing-today/code (git grep for validateCrawlUrl/validate_crawl_url in the opencode, openchamber and dezren39/nix clones finds no twin), so this is a single-repo issue.

Acceptance criteria

• validate_crawl_url refuses a host containing DEL (0x7F), a C1 control (0x80–0x9F), NBSP (0xA0), or any of < > ^ |, up front with a clear validator error.
• Controls unchanged: ordinary DNS names, exam_ple.com, valid IDN hosts, valid IPv6 literals and public targets are still accepted on both sides.
• A regression test in pkgs/lab-ops-hub/test/test_container_validate.py covers each refused class, and fails with only container/app.py reverted (ablation).
• The Python and TS validators agree on the full character battery above.