feat: launch Gemini 3 Flash in Gemini CLI ⚡️⚡️⚡️ (#15196)

Co-authored-by: gemini-cli-robot <gemini-cli-robot@google.com>
Co-authored-by: joshualitt <joshualitt@google.com>
Co-authored-by: Sehoon Shon <sshon@google.com>
Co-authored-by: Adam Weidman <65992621+adamfweidman@users.noreply.github.com>
Co-authored-by: Adib234 <30782825+Adib234@users.noreply.github.com>
Co-authored-by: Jenna Inouye <jinouye@google.com>

packages/cli/src/zed-integration/zedIntegration.ts

@@ -283,7 +283,6 @@ export class Session {
 
       try {
         const model = getEffectiveModel(
-          this.config.isInFallbackMode(),
           this.config.getModel(),
           this.config.getPreviewFeatures(),
         );