fix(config): fix duplicate model in /model picker for haiku/opus-only tenants (EPMCDME-12779)

[Sergei-Nikitin-epam]

Summary

• Root cause: `autoSelectModelTiers()` set `sonnetModel` only when `selectedModel.includes('sonnet')`. Selecting haiku as primary left `sonnetModel` undefined even when the tenant had real sonnet models, so `ANTHROPIC_DEFAULT_SONNET_MODEL` was never set and Claude Code fell back to the haiku model ID for the Custom Sonnet slot — producing a duplicate entry in `/model`.
• Fix: Apply the same models-list auto-selection for the sonnet tier as already done for haiku and opus: filter by the `'sonnet'` keyword and pick the latest version regardless of which tier was chosen as primary.
• Also re-introduces the opus-only and haiku-only tenant routing that was reverted in Revert "fix(config): correct model-tier assignment and subagent routing for opus-only tenants" #423, with the haiku-only case added:
  • Opus-only: set only `CLAUDE_CODE_SUBAGENT_MODEL` (not `ANTHROPIC_DEFAULT_SONNET_MODEL`) to prevent opus appearing in both Custom Sonnet and Custom Opus slots.
  • Haiku-only: route haiku through the sonnet slot and omit `ANTHROPIC_DEFAULT_HAIKU_MODEL` to prevent haiku appearing in both slots.

Files changed

File	Change
`src/cli/commands/setup.ts`	`autoSelectModelTiers()` — sonnet now auto-selects from models list like haiku/opus
`src/agents/core/BaseAgentAdapter.ts`	`transformEnvVars()` — opus-only and haiku-only slot routing
`src/providers/plugins/bedrock/bedrock.template.ts`	Bedrock hook — same opus-only / haiku-only fallback branches
`src/cli/commands/tests/model-tier-auto-selection.test.ts`	New tests: haiku-primary-with-sonnet and no-sonnet-in-list cases
`src/agents/core/tests/model-tier-config.test.ts`	Updated haiku-only test to reflect sonnet-slot routing

Test plan

• `npm run test -- model-tier-auto-selection` — new EPMCDME-12779 test cases pass
• `npm run test -- model-tier-config` — haiku-only routing test passes
• Manual: run `codemie setup` with haiku as primary model on a tenant that also provisions sonnet → `/model` picker shows correct distinct IDs in Custom Haiku and Custom Sonnet slots
• Manual: opus-only tenant → no duplicate in Custom Sonnet / Custom Opus slots
• Manual: haiku-only tenant → model appears once (in sonnet slot), no duplicate

Closes EPMCDME-12779

[yanaSelin]

Code Review — 3 findings (2 critical, 1 major)

The fix correctly addresses the duplicate-model-in-/model-picker symptom in the common case, but two bugs in the surrounding code mean the fix doesn't work for existing users who already have a saved profile or a populated shell environment.

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CR-001 [CRITICAL] — src/cli/commands/setup.ts:299-301 — Stale tier config survives re-setup

// setup.ts lines 299-301 (NOT changed by this PR)
if (modelTiers.haikuModel) config.haikuModel = modelTiers.haikuModel;
if (modelTiers.sonnetModel) config.sonnetModel = modelTiers.sonnetModel;
if (modelTiers.opusModel) config.opusModel = modelTiers.opusModel;

When autoSelectModelTiers() returns { sonnetModel: undefined } (e.g. an opus-only tenant), the if (modelTiers.sonnetModel) guard is falsy, so the assignment is skipped and the existing config.sonnetModel from the saved profile is left unchanged. exportProviderEnvVars then emits it as CODEMIE_SONNET_MODEL = 'claude-sonnet-4-6', and transformEnvVars hits the "distinct sonnet tier" branch — the new opus-only routing never applies.

Any user re-running codemie setup to switch to an opus-only or haiku-only tenant will still see the duplicate.

Fix: Remove the if guards; assign unconditionally:

config.haikuModel = modelTiers.haikuModel;
config.sonnetModel = modelTiers.sonnetModel;
config.opusModel = modelTiers.opusModel;

---

CR-002 [CRITICAL] — src/cli/commands/setup.ts:587-597 — Early-return bypasses new auto-selection logic when shell has stale env vars

// setup.ts lines 587-597 (NOT changed by this PR)
if (envHaiku && envSonnet && envOpus) {
  return { haikuModel: envHaiku, sonnetModel: envSonnet, opusModel: envOpus };
}

autoSelectModelTiers() reads ANTHROPIC_DEFAULT_HAIKU_MODEL, ANTHROPIC_DEFAULT_SONNET_MODEL, and ANTHROPIC_DEFAULT_OPUS_MODEL directly from the process environment. If all three are set in the shell — which is the normal state after any prior multi-tier session — the function returns immediately with the old values. The new else if (sonnetModels.length > 0) and else { // no sonnet tier } branches are never reached. The config.ts empty-string override only covers CODEMIE_* vars, not the ANTHROPIC_DEFAULT_* vars that this early-return reads.

This means the fix is entirely bypassed for users who have run codemie setup before.

Fix: Either remove the early-return, or validate that the env vars are consistent with the models list before trusting them (e.g. skip envSonnet if models contains no sonnet-keyword entry).