feat: add AIHubMix provider (#865)

* feat: add AIHubMix provider

* feat: load AIHubMix models dynamically

* feat: polish AIHubMix model setup

* feat: send AIHubMix app code

* docs: remove redundant AIHubMix recommendation

---------

Co-authored-by: LL <13697272357@163.com>

lib/aihubmix-models.ts

@@ -0,0 +1,79 @@
+export const AIHUBMIX_MODELS_ENDPOINT = "https://aihubmix.com/api/v1/models"
+
+const NON_CHAT_MODEL_TYPES = new Set([
+    "embedding",
+    "image_generation",
+    "rerank",
+    "transcription",
+    "tts",
+    "video",
+])
+
+type AihubmixModelListPayload = {
+    data?: unknown
+}
+
+type AihubmixModelRecord = {
+    model_id?: unknown
+    types?: unknown
+}
+
+function getModelTypes(types: unknown): Set<string> {
+    if (typeof types !== "string") {
+        return new Set()
+    }
+
+    return new Set(
+        types
+            .split(",")
+            .map((type) => type.trim())
+            .filter(Boolean),
+    )
+}
+
+function isChatModel(record: AihubmixModelRecord): record is {
+    model_id: string
+    types: string
+} {
+    if (typeof record.model_id !== "string" || !record.model_id.trim()) {
+        return false
+    }
+
+    const types = getModelTypes(record.types)
+    if (!types.has("llm")) {
+        return false
+    }
+
+    return !Array.from(NON_CHAT_MODEL_TYPES).some((type) => types.has(type))
+}
+
+export function extractAihubmixModelIds(payload: unknown): string[] {
+    const data = (payload as AihubmixModelListPayload)?.data
+    if (!Array.isArray(data)) {
+        return []
+    }
+
+    const seen = new Set<string>()
+    const modelIds: string[] = []
+
+    for (const item of data) {
+        if (!item || typeof item !== "object") {
+            continue
+        }
+
+        const record = item as AihubmixModelRecord
+        if (!isChatModel(record)) {
+            continue
+        }
+
+        const modelId = record.model_id.trim()
+        if (seen.has(modelId)) {
+            continue
+        }
+
+        seen.add(modelId)
+        modelIds.push(modelId)
+    }
+
+    return modelIds
+}