bump library/ubuntu from 24.04 to 26.04 in /pods

Bumps library/ubuntu from 24.04 to 26.04.

---
updated-dependencies:
- dependency-name: library/ubuntu
  dependency-version: '26.04'
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pods/Containerfile

@@ -11,7 +11,7 @@
 # BYO key: nothing here carries credentials. A member exports their own
 # ANTHROPIC_API_KEY / OPENAI_API_KEY (or runs the tools' login flow); the keys
 # live in their persisted home, never in the image.
-FROM docker.io/library/ubuntu:24.04
+FROM docker.io/library/ubuntu:26.04
 
 ENV DEBIAN_FRONTEND=noninteractive