Feat #617 : Add Python callback interface tutorial and related scripts for elastic-tube-1d

[kishansinghifs1]

Add Python callback interface tutorial and related scripts for elastic-tube-1d #617

1. Added a complete Python callback interface workflow (precice-config-callback.xml, solver wrappers, and run scripts) alongside the baseline elastic tube case without modifying existing functionality.
2. Created pressureRampAction.py with a performAction(...) function that applies a time-dependent pressure ramp (t < 0.2) via the preCICE Python callback interface.

Checklist:

• I added a summary of any user-facing changes (compared to the last release) in the changelog-entries/<PRnumber>.md.
• I will remember to squash-and-merge, providing a useful summary of the changes of this PR.