Update to 3.38.5

[Copilot]

Auto-generated update for Flutter SDK 3.38.5 stable release (published Dec 11, 2025).

Type of change

• bug fix
• new feature
• code style / documentation

What does this implement/fix? Explain your changes.

Updates Flutter SDK version across repository:

• Dockerfile: FLUTTER_VERSION="3.38.5"
• README.md: Version badge, release link, and all CI examples (CircleCI, Travis CI, GitLab CI)

Download URL: https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.38.5-stable.tar.xz

Note: Close and reopen PR to trigger precheck pipeline.

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://storage.googleapis.com/flutter_infra_release/releases/releases_linux.json
  • Triggering command: /usr/bin/curl curl -s REDACTED (http block)
  • Triggering command: /usr/bin/curl curl -sL REDACTED (http block)
• https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.38.5-stable.tar.xz
  • Triggering command: /usr/bin/curl curl -I --silent --location REDACTED (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)