Replace automatic SMW rebuildData with user notification

[cicalese]

Summary

• Removes the automatic rebuildData.php call from container startup
• Replaces it with a notification message when SMW is newly set up, telling the user to run it manually
• The SMW state snapshot logic is preserved for detection purposes

Problem

rebuildData.php ran synchronously during startup, blocking the web server, log permissions, and php-fpm from starting. On large wikis this could take hours, leaving the site completely down. Additionally, large wikis need control over rebuild options (--startidfile, page ranges, etc.) that can't be automated.

Approach

Instead of running rebuildData.php automatically, detect when SMW was newly set up (by comparing .smw.json before and after run_autoupdate) and print a message:

========================================================================
NOTE: Semantic MediaWiki was newly set up. You need to run rebuildData
to populate the SMW store. Use: canasta maintenance smw-rebuild
========================================================================

A CLI command (canasta maintenance smw-rebuild) will be added in a follow-up PR.

Fixes #91

Test plan

• Build CanastaBase image with this change, then build Canasta image on top
• Create a new installation with SMW enabled
• Verify the notification message appears in docker compose logs
• Verify the web server starts promptly without waiting for SMW rebuild
• Verify SMW tables are created (by setupStore.php via update.php hooks) but data is not populated until the user runs rebuildData.php manually

[github-actions]

🐳 The image based on d96ebb14 commit has been built with 1.43.6-20260213-92 tag as ghcr.io/canastawiki/canasta-base:1.43.6-20260213-92

[yaronkoren]

That final note to the user might not be fully correct, but this looks good enough for now!