Remove freePlanModel and opencodeBackupModel settings

Users now use OpenCode Models (Fallback Chain) for model selection.
- Removed Auto Model for Hobby/Free Plan section from admin panel
- Removed OpenCode Ultimate Backup Model section from admin panel
- Updated server to use opencodeModels for free plan users
- Removed backup model fallback logic (opencodeModels chain handles this)

chat/server.js

@@ -1542,13 +1542,11 @@ let mistralSettings = {
 const PLANNING_PROVIDERS = ['openrouter', 'mistral', 'google', 'groq', 'nvidia', 'ollama', 'cohere', 'kilo'];
 let planSettings = {
   provider: 'openrouter', // legacy field, retained for backwards compatibility
-  freePlanModel: '',
   planningChain: [], // [{ provider, model }]
 };
 let providerLimits = {
   limits: {},
   modelProviders: {},
-  opencodeBackupModel: '',
 };
 let pendingProviderPersistTimer = null;
 let providerUsage = {};
@@ -4927,10 +4925,8 @@ function resolvePlanModel(plan, requestedModel) {
   
   const candidateList = getConfiguredModels();
   
-  // For hobby/free plan users, use the admin-configured auto model
+  // For hobby/free plan users, use the first model from the fallback chain
   if (normalized === 'hobby') {
-    const adminDefault = (planSettings.freePlanModel || '').trim();
-    if (adminDefault) return adminDefault;
     const firstModel = candidateList[0];
     if (firstModel) return firstModel.name;
     return resolveFallbackModel();
@@ -5890,9 +5886,6 @@ async function loadPlanSettings() {
       if (typeof parsed.provider === 'string' && PLANNING_PROVIDERS.includes(normalizeProviderName(parsed.provider))) {
         planSettings.provider = normalizeProviderName(parsed.provider);
       }
-      if (typeof parsed.freePlanModel === 'string') {
-        planSettings.freePlanModel = parsed.freePlanModel.trim();
-      }
       if (Array.isArray(parsed.planningChain)) {
         planSettings.planningChain = normalizePlanningChain(parsed.planningChain);
       }
@@ -6178,7 +6171,6 @@ async function loadProviderLimits() {
   }
   
   collectProviderSeeds().forEach((p) => ensureProviderLimitDefaults(p));
-  if (!providerLimits.opencodeBackupModel) providerLimits.opencodeBackupModel = '';
 }
 
 async function persistProviderLimits() {
@@ -8764,16 +8756,6 @@ function buildPlanModelChain() {
   const chain = normalizePlanningChain(planSettings.planningChain);
   if (chain.length) return chain;
 
-  // Check if freePlanModel has a provider prefix (e.g., "groq/compound-mini")
-  const freePlanModel = (planSettings.freePlanModel || '').trim();
-  if (freePlanModel) {
-    const parsed = parseModelString(freePlanModel);
-    if (parsed.provider) {
-      // User specified a provider prefix, use it directly
-      return [{ provider: parsed.provider, model: parsed.model }];
-    }
-  }
-
   return defaultPlanningChainFromSettings(planSettings.provider);
 }
 
@@ -10893,16 +10875,6 @@ async function sendToOpencodeWithFallback({ session, model, content, message, cl
     if (result) return result;
   }
 
-  const backupModel = (providerLimits.opencodeBackupModel || '').trim();
-  if (backupModel) {
-    const backupChain = buildOpencodeAttemptChain(cliName, backupModel);
-    for (const option of backupChain) {
-      const result = await tryOption(option, true);
-      if (result instanceof Error) break;
-      if (result) return result;
-    }
-  }
-
   const MAX_EARLY_TERMINATIONS = 2;
   const recentEarlyTerminations = attempts.filter(
     a => a.earlyTermination &&
@@ -16054,9 +16026,6 @@ async function handleAdminPlanSettingsPost(req, res) {
     if (Array.isArray(body.planningChain)) {
       planSettings.planningChain = normalizePlanningChain(body.planningChain);
     }
-    if (typeof body.freePlanModel === 'string') {
-      planSettings.freePlanModel = body.freePlanModel.trim();
-    }
     if (!planSettings.planningChain.length) {
       planSettings.planningChain = defaultPlanningChainFromSettings(planSettings.provider);
     }
@@ -16142,7 +16111,6 @@ async function handleAdminProviderLimitsGet(req, res) {
     sendJson(res, 200, {
       limits: providerLimits.limits,
       usage: snapshot,
-      opencodeBackupModel: providerLimits.opencodeBackupModel || '',
       providers: discovery.providers,
       providerModels: discovery.providerModels,
     });
@@ -16168,17 +16136,12 @@ async function handleAdminProviderLimitsPost(req, res) {
       if (body[field] !== undefined) target[field] = sanitizeLimitNumber(body[field]);
     });
 
-    if (typeof body.opencodeBackupModel === 'string') {
-      providerLimits.opencodeBackupModel = body.opencodeBackupModel.trim();
-    }
-
     await persistProviderLimits();
     const discovery = await discoverProviderModels();
     sendJson(res, 200, {
       ok: true,
       limits: providerLimits.limits,
       usage: getProviderUsageSnapshot(discovery.providers),
-      opencodeBackupModel: providerLimits.opencodeBackupModel || '',
       providers: discovery.providers,
       providerModels: discovery.providerModels,
     });
@@ -19362,7 +19325,6 @@ async function bootstrap() {
   });
   console.log('[CONFIG] Planning Settings:', {
     provider: planSettings.provider,
-    freePlanModel: planSettings.freePlanModel || 'not set',
     planningChainLength: planSettings.planningChain?.length || 0,
     planningChain: planSettings.planningChain
   });