feat(examples): Introduce new Java 25 example

[lupsalexandra33]

This PR adds a new example for running a simple HTTP server using Java 25.

Files Added:

• SimpleHttpServer.java: The application source code.
• Dockerfile: Build rules, using the openjdk:25-rc-oraclelinux9 base image.
• Kraftfile: Defines dependencies, and sets the Java 25 runtime path and entrypoint.
• README.md: Instructions to set up and use the example.

[razvand]

Looks good. See my comments. Apart from these, all is well. I need to test.

Convert this PR from draft PR to a full PR.

[razvand]

Squash both commits into a single one.

The Kraftfile must be an example Kraftfile, a smaller one, not the current Kraftfile, which is a big one.

Take a look into PR #239 . Ideally that's what you would have:

• A library commit in library/java/25/.
• An example commit in examples/httpserver-java25/.
• An example commit using the base runtime in examples/httpserver-java25-base/.

[razvand]

Sign-off your commits.

See my comments.

Test your work.

Be patient, careful and rigorous.

[razvand]

Remove these.

Add runtime: base:latest.

Look into other ...-base/ directories, see how the Kraftfile looks like.

Test your work. I followed the instructions in the README.md for your work and it didn't work.

Pay attention. Be patient. Be rigorous. Test. Test again. Make it good.

[razvand]

Same as above, this goes away.

Add a line runtime: java:25.