test(providers): pin openaicompat providers off adaptive thinking (M7)

Adaptive thinking (thinking.type=adaptive + output_config.effort) is an
Anthropic-protocol mode the langchaingo OpenAI transport cannot emit, and
the openaicompat Call path never threads PrepareAdaptiveCallOptions. So an
adaptive reasoning mode declared in an openaicompat provider's models.yml
would silently no-op.

Assert that none of the openaicompat-backed providers (qwen, glm, deepseek,
kimi, minimax) resolve to adaptive thinking for any agent type. The day
someone adds an adaptive model/mode to one of their configs, this fails
loudly instead of dropping the thinking budget in silence.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/pkg/providers/openaicompat_adaptive_test.go

@@ -0,0 +1,45 @@
+package providers
+
+import (
+	"testing"
+
+	"pentagi/pkg/providers/deepseek"
+	"pentagi/pkg/providers/glm"
+	"pentagi/pkg/providers/kimi"
+	"pentagi/pkg/providers/minimax"
+	"pentagi/pkg/providers/pconfig"
+	"pentagi/pkg/providers/qwen"
+)
+
+func TestOpenAICompatProvidersDoNotUseAdaptiveThinking(t *testing.T) {
+	t.Parallel()
+
+	providers := []struct {
+		name   string
+		config func() (*pconfig.ProviderConfig, error)
+		models func() (pconfig.ModelsConfig, error)
+	}{
+		{"qwen", qwen.DefaultProviderConfig, qwen.DefaultModels},
+		{"glm", glm.DefaultProviderConfig, glm.DefaultModels},
+		{"deepseek", deepseek.DefaultProviderConfig, deepseek.DefaultModels},
+		{"kimi", kimi.DefaultProviderConfig, kimi.DefaultModels},
+		{"minimax", minimax.DefaultProviderConfig, minimax.DefaultModels},
+	}
+
+	for _, p := range providers {
+		cfg, err := p.config()
+		if err != nil {
+			t.Fatalf("%s: DefaultProviderConfig() error: %v", p.name, err)
+		}
+		models, err := p.models()
+		if err != nil {
+			t.Fatalf("%s: DefaultModels() error: %v", p.name, err)
+		}
+
+		for _, opt := range pconfig.AllAgentTypes {
+			if cfg.UsesAdaptiveThinking(models, opt) {
+				t.Errorf("%s/%s resolves to adaptive thinking, but the openaicompat transport never emits it (M7): adaptive thinking is Anthropic/Bedrock-only", p.name, opt)
+			}
+		}
+	}
+}