feat(orchestrator): add retry-on-fallback and provider init timeout

Adds retryOnFallback (retry failed builds on alternate provider) and
providerInitTimeout (swap provider if init takes too long). Refactors
run() into run()/runWithProvider() to support retry loop.

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

src/model/orchestrator/options/orchestrator-options.ts

@@ -156,6 +156,14 @@ class OrchestratorOptions {
     return Number(OrchestratorOptions.getInput('runnerCheckMinAvailable')) || 1;
   }
 
+  static get retryOnFallback(): boolean {
+    return OrchestratorOptions.getInput('retryOnFallback') === 'true';
+  }
+
+  static get providerInitTimeout(): number {
+    return Number(OrchestratorOptions.getInput('providerInitTimeout')) || 0;
+  }
+
   static get containerCpu(): string {
     return OrchestratorOptions.getInput('containerCpu') || `1024`;
   }