Lesson Summary children routes refactor

[AlexVelezLl]

Summary

1. Moves lesson edit children routes to be children of the LessonSummaryPage.
2. Updates SidePanel render pattern according to Quiz creation side panels improvements #12819
3. Moves router view from lesson creation to LessonSummaryPage.

[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-0.18.0.dev0_git.20241118144421.pex
Windows Installer (EXE)	kolibri-0.18.0.dev0+git.20241118144421-windows-setup-unsigned.exe
Debian Package	kolibri_0.18.0.dev0+git.20241118144421-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.18.0.dev0+git.20241118144421.dmg
Android Package (APK)	kolibri-0.18.0.dev0+git.20241118144421-0.1.4-debug.apk
TAR file	kolibri-0.18.0.dev0+git.20241118144421.tar.gz
WHL file	kolibri-0.18.0.dev0+git.20241118144421-py2.py3-none-any.whl

[AllanOXDi]

Just noting that this WIP PR #12845 is blocking it. Please do not merge it yet

[marcellamaki]

@AlexVelezLl - this looks good to me. I am thinking through the best order of operations for open PRs (including what you were saying about the handlers earlier) and I need to check in with @AllanOXDi about his comment above, so not merging yet. But it all looks good to me, and the manual testing of the moved side panels seems to work well.