fix(ops): propagate scale-out restore environment

[leon-ape]

Fixes #10815.

Release 1.0 counterpart of #10817.

Problem

During horizontal scale-out from a Backup, scaleOut.fromBackup.restoreEnv is dropped before the generated Restore is created.

Changes

• add an explicit RestoreManager setter for user-provided Restore environment
• pass FromBackup.restoreEnv into the scale-out Restore plan
• verify Restore.spec.env in focused plan and Operations coverage

Scope

This PR only propagates restore environment on release-1.0. It does not change Backup validation, namespaces, authorization, VolumeSnapshot behavior, or source-target selection.

Validation

• scripts/codex-go-test.sh ./pkg/controller/plan -count=1
• scripts/codex-go-test.sh ./pkg/operations -count=1
• git diff --check

[apecloud-bot]

Auto Cherry-pick Instructions

Usage:
  - /nopick: Not auto cherry-pick when PR merged.
  - /pick: release-x.x [release-x.x]: Auto cherry-pick to the specified branch when PR merged.

Example:
  - /nopick
  - /pick release-1.1

CLA Recheck Instructions

Usage:
  - /recheck-cla: Trigger a re-check of CLA status for this pull request.
Example:
  - /recheck-cla

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 54.31%. Comparing base (c55a6d5) to head (c069e2c).
⚠️ Report is 1 commits behind head on release-1.0.

Additional details and impacted files

@@               Coverage Diff               @@
##           release-1.0   #10823      +/-   ##
===============================================
+ Coverage        54.17%   54.31%   +0.13%     
===============================================
  Files              495      495              
  Lines            55939    55948       +9     
===============================================
+ Hits             30305    30387      +82     
+ Misses           22624    22571      -53     
+ Partials          3010     2990      -20     

Flag	Coverage Δ
unittests	54.31% <100.00%> (+0.13%)	⬆️

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

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[leon-ape]

/approve