docs(roadmap): add #451 — models list/help --output-format json hang with zero stdout

[Yeachan-Heo]

ROADMAP pinpoint #451

Dogfooded for the 2026-05-24 04:00 Clawhip pinpoint nudge (message 1507956340130316460).

Repro (local ./rust/target/debug/claw git_sha 003b739d, origin/main f8e1bb72 — models dispatch path is not touched by 63ce483c..f8e1bb72 which are docs-only ROADMAP additions)

timeout 6 ./rust/target/debug/claw models list --output-format json   # exit=124, stdout=0, stderr=0
timeout 6 ./rust/target/debug/claw models --help --output-format json # exit=124, stdout=0, stderr=0

Also reproduces in a clean isolated HOME ({} settings, no plugins).

Positive controls (same binary)

./rust/target/debug/claw version --output-format json # exit=0, valid JSON
./rust/target/debug/claw doctor --output-format json  # exit=0, valid JSON

Why this is distinct from existing items

• 合影留念 #322 (deprecation warnings on stderr breaking JSON parse): repros with zero stdout bytes, not a warning preceding parseable JSON.
• 合影留念 #355 (session list/session help JSON hang): different surface; this is the model provider/registry discovery path.
• 合影 #449/合影 #450 (session list auth routing, prompt missing_credentials on stderr): unrelated paths; both doctor and version JSON return promptly here.

Why it matters

Model registry inspection is a preflight clawability surface. Before invoking prompt, claws must resolve --model <alias> to a concrete provider, decide which credential env var to ask for, and present a model menu. If models list and models --help silently deadlock at zero bytes, automation cannot distinguish "no models configured", "provider discovery slow", "missing credentials", "deprecated config blocking load", or "dispatch deadlock".

See ROADMAP entry for the full required fix shape (a–d): static stdout JSON envelopes, no provider network probes during help/list, typed per-model status:"unavailable" instead of full-response timeout, deterministic-budget regression coverage on Anthropic + one OpenAI-compatible profile.

—
[repo owner's gaebal-gajae (clawdbot) 🦞]

[code-yeongyu]

Content merged to main via batch commit c881069. Closing PR.