feat(models): offer the Claude 5 family only, default to Sonnet 5

[aaronjmars]

What

Cuts the Anthropic model picker down to the current Claude 5 family and moves the default to Sonnet 5.

	before	after
default	claude-sonnet-4-6	claude-sonnet-5
offered	sonnet-4-6, opus-4-8, opus-4-7, fable-5, sonnet-5, haiku-4-5	sonnet-5, opus-5, haiku-4-5

claude-opus-5 was never in the picker despite Fable 5 and Sonnet 5 being there, so the newest Opus on offer was 4.8.

Why it touches 16 files

The default resolves in six independent places. Miss one and an instance that never opens the picker silently keeps resolving a removed id: MODELS[0], aeon.yml model:, the config.ts parse fallback, the page.tsx useState seed, and the CONFIG_MODEL fallbacks in both aeon.yml and messages.yml.

Three skills generate config and were recommending removed ids - create-skill's default model recommendation, feature's "current models (suggest these as replacements)" list, and skill-repair's timeout downgrade. Left alone they would keep writing ids that 422 at dispatch. Retargeted to Haiku 4.5 for cost cases, Opus 5 for reasoning-heavy ones.

Gateway fixes (verified against live provider catalogs)

openrouter - slot defaults moved to anthropic/claude-opus-5 / anthropic/claude-sonnet-5, both confirmed present in OpenRouter's public catalog.

venice - fixes a latent 404 that predates this PR. Venice carries no haiku model at all, but claude-haiku-4-5 was in the allowlist. Selecting Haiku 4.5, a live picker option, matched and routed to a model Venice has never had, bypassing the safe fallback that existed to catch exactly that case. Allowlist rewritten to the 9 Claude ids Venice actually carries, fallback moved from opus-4-6 to sonnet-5.

Routing now, exercising the real case statement:

claude-sonnet-5           -> claude-sonnet-5     (was opus-4-6, needless downgrade)
claude-opus-5             -> claude-opus-5       (was opus-4-6, needless downgrade)
claude-haiku-4-5-20251001 -> claude-sonnet-5     (was claude-haiku-4-5 -> 404)
claude-opus-4-8           -> claude-opus-4-8     (back-compat preserved)
bogus-model               -> claude-sonnet-5     (fallback intact)

Also flips the GROK_MODEL gateway default from grok-build-0.1 to grok-4.5, so the gateway and CLI paths name the same model.

Verification

• 165/165 dashboard tests, tsc --noEmit clean
• validate-config.js CLEAN (62 skills)
• test_run_grok.sh ALL PASS (incl. the 6 OAuth-refresh cases from fix(grok): persist rotated OAuth refresh token so GROK_CREDENTIALS survives past 6h #773)
• actionlint + shellcheck -S error clean
• Bidirectional check that every picker id across all 6 harness lists (18 ids) appears in the workflow choice options and vice versa, so nothing can 422 and no dead option remains

Deliberately unchanged

skills/fork-fleet/SKILL.md keeps claude-sonnet-4-6 in two report templates - those are placeholder values describing config read from other forks, which legitimately pin older ids.

Separate follow-up, not fixed here

harness-adapter/README.md points contributors upstream to aaronjmars/harness-adapter for fixes and says three more harnesses (opencode, copilot, agy) plus the live test suite live there. That repo does not exist - 404 from the API and raw host, absent from an authenticated repo listing, and not in global search. Worth correcting the README separately.