Backport release/v6.7: Initialize app from last header when a frozen node restarts

[seidroid]

Backport of #4447 to release/v6.7.

[seidroid]

Please cherry-pick the changes locally and resolve any conflicts.

git fetch origin backport-4447-to-release/v6.7
git worktree add --checkout .worktree/backport-4447-to-release/v6.7 backport-4447-to-release/v6.7
cd .worktree/backport-4447-to-release/v6.7
git reset --hard HEAD^
git cherry-pick -x d4853e532b878fe34033ff63495521c782baf0fb
git push --force-with-lease

[github-actions]

The latest Buf updates on your PR. Results from workflow Buf / buf (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Oct 8, 2026, 9:14 AM

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.80%. Comparing base (fccc24e) to head (e3d34c8).

Additional details and impacted files

@@               Coverage Diff                @@
##           release/v6.7    #4507      +/-   ##
================================================
- Coverage         61.84%   60.80%   -1.04%     
================================================
  Files              2168     2068     -100     
  Lines            188740   176780   -11960     
================================================
- Hits             116727   107492    -9235     
+ Misses            61159    59405    -1754     
+ Partials          10854     9883     -971     

Flag	Coverage Δ
sei-db	69.80% <ø> (ø)
sei-db-state-db	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
sei-tendermint/node/node.go	66.59% <ø> (ø)

... and 100 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.