Feature: Add local OpenAI-compatible model discovery to /model (#201)

* Add local OpenAI-compatible model discovery to /model

* Guard local OpenAI model discovery from Codex routing

* Preserve remote OpenAI Codex alias behavior

src/utils/model/modelOptions.ts

@@ -1,5 +1,6 @@
 // biome-ignore-all assist/source/organizeImports: internal-only import markers must not be reordered
 import { getInitialMainLoopModel } from '../../bootstrap/state.js'
+import { getAdditionalModelOptionsCacheScope } from '../../services/api/providerConfig.js'
 import {
   isClaudeAISubscriber,
   isMaxSubscriber,
@@ -44,6 +45,25 @@ export type ModelOption = {
   descriptionForModel?: string
 }
 
+function getScopedAdditionalModelOptions(): ModelOption[] {
+  const config = getGlobalConfig()
+  const activeScope = getAdditionalModelOptionsCacheScope()
+
+  if (!activeScope) {
+    return []
+  }
+
+  if (config.additionalModelOptionsCacheScope !== undefined) {
+    return config.additionalModelOptionsCacheScope === activeScope
+      ? (config.additionalModelOptionsCache ?? [])
+      : []
+  }
+
+  return activeScope === 'firstParty'
+    ? (config.additionalModelOptionsCache ?? [])
+    : []
+}
+
 export function getDefaultOptionForUser(fastMode = false): ModelOption {
   if (process.env.USER_TYPE === 'ant') {
     const currentModel = renderDefaultModelSetting(
@@ -408,6 +428,16 @@ function getModelOptionsBase(fastMode = false): ModelOption[] {
     return standardOptions
   }
 
+  if (getAdditionalModelOptionsCacheScope()?.startsWith('openai:')) {
+    const activeOpenAIOptions = getActiveOpenAIModelOptionsCache()
+    return [
+      getDefaultOptionForUser(fastMode),
+      ...(activeOpenAIOptions.length > 0
+        ? activeOpenAIOptions
+        : getScopedAdditionalModelOptions()),
+    ]
+  }
+
   // PAYG 1P API: Default (Sonnet) + Sonnet 1M + Opus 4.6 + Opus 1M + Haiku
   if (getAPIProvider() === 'firstParty') {
     const payg1POptions = [getDefaultOptionForUser(fastMode)]
@@ -566,13 +596,8 @@ export function getModelOptions(fastMode = false): ModelOption[] {
     })
   }
 
-  const additionalOptions =
-    getAPIProvider() === 'openai'
-      ? getActiveOpenAIModelOptionsCache()
-      : getGlobalConfig().additionalModelOptionsCache ?? []
-
-  // Append additional model options fetched during bootstrap/endpoints.
-  for (const opt of additionalOptions) {
+  // Append additional model options fetched during bootstrap
+  for (const opt of getScopedAdditionalModelOptions()) {
     if (!options.some(existing => existing.value === opt.value)) {
       options.push(opt)
     }