[86ed0eab] Panel routing surface for hummin/Nebius/OpenRouter providers

[roboco-app]

Close the panel↔backend provider seam: the trunk's derive_mode() now returns 'hummin' (9bc712e) and the roster grew to include hummin (e3c27b2, #1104), Nebius, and OpenRouter (synced by 40bd83c), but the panel snapshot has none of the three anywhere — RoutingMode union in panel/src/lib/api/providers.ts is frozen at anthropic|grok|codex|gemini|kimi|ollama|self_hosted|mix|cost_tiered, and ModelProvider in panel/src/types/index.ts is the pre-hummin seven values. The same unreachable-from-panel class #661 fixed for Codex/Gemini.

IMPORTANT: the intake snapshot was 226 commits behind origin/slave tip 929a8cc — FIRST re-verify against live trunk: (a) the exact provider ids/enum values in the backend (source of truth — copy them, never guess), (b) which of the three new providers ship apply* branches in ModelRoutingService (apply-capable) vs mix-only, (c) the backend's live interactive-roles exclusion list for Intake/Secretary — hummin is intake-capable per the intake bridge work (23cecc8).

Then build, all four deliverables:

1. Mode section renders every derive_mode value with a correct label, including 'hummin' — no unknown/blank.
2. Mode buttons: one-click apply-capable mode button per new provider, mirroring the existing Codex/Gemini/Kimi card structure (fix: post-finale completeness sweep — routing surface, provider config, budgets, compose env, interactive exemption #661 pattern). Mix-only providers get an explicit card hint saying so — never a dead button.
3. Vocabulary: ModelProvider in panel/src/types, the per-agent mix picker, and the complexity-override model dropdown cover hummin/nebius/openrouter, with interactive-role exclusions matching the backend live list exactly.
4. Round-trip check per new provider: apply its mode via POST /providers, then GET /providers — the panel renders the same mode label derive_mode returns, with the expected assignment snapshot.

Constraints: copy provider ids/enum values from the live backend (the round-trip check catches drift); if you find a genuine backend gap, flag it back to fe-pm rather than working around it in panel code. Placement per the architectural standard: types in panel/src/types, API client in panel/src/lib/api, cards in panel/src/components. Run pnpm format/lint/typecheck/test before submit; coverage target 80%.

Note: prior panel work on OpenRouter (key status + model search, see learnings lrn-75e63984/lrn-5de81a62) may already exist on trunk — check before re-implementing anything; the prior QA lesson found the panel gating ModeButton on a key-status shape that didn't match the backend, so verify the key-status contract before gating any button.

[github-actions]

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