fix: notification handling for share removal and space membership expiry

[maki5]

Notifications service

• Handle the ShareRemoved event (backport of feat: Add email notification for share removed owncloud/ocis#10915):
  new email template, event dispatch and grouped-mail support, and the
  mail option is enabled by default in the notification settings
• Rework handleSpaceMembershipExpired: resolve the space name via a
  prepare helper and send from the default email sender, dropping the
  dependency on the unresolvable space owner lookup

Userlog service

• Add a dedicated conversion path for SpaceMembershipExpired that
  resolves only the space (the template does not reference a user),
  so the in-app notification no longer fails on the unresolvable space
  owner placeholder
• Handle policy violation and antivirus postprocessing steps for
  granular in-app notifications (previously we didn't handle it's disabling)

Dependencies

• Bump reva to v2.48.1-0.20260812174127-12b756ed83c5 (PR
  Backport and fix of space membership expired event reva#766), bringing:
  • Backport of [full-ci] Fix the SpaceMembershipExpired event owncloud/ocis#11079: emit a SpaceMembershipExpired
    event when the decomposedfs cleans up expired space grants "on
    access"
  • Sharing manager fix: publish SpaceMembershipExpired instead of
    ShareExpired for expired space-root shares

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Metrics 0 complexity · 26 duplication

Metric	Results
Complexity	0
Duplication	26

View in Codacy

🟢 Coverage 39.04% diff coverage · +0.02% coverage variation

Metric	Results
Coverage variation	✅ +0.02% coverage variation (-1.00%)
Diff coverage	✅ 39.04% diff coverage

View coverage diff in Codacy

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (8478b5d)	84082	19349	23.01%
Head commit (1cbc833)	84206 (+124)	19397 (+48)	23.04% (+0.02%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#3257)	146	57	39.04%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

_{NEW Get contextual insights on your PRs based on Codacy's metrics, along with PR and Jira context, without leaving GitHub. Enable AI reviewer
TIP This summary will be updated as you push new changes.}

[micbar]

Please add a description.

[micbar]

Looking good to me 👍

[micbar]

the last merge from main somehow messed this up a bit.

@butonic @pbleser-oc Can you help to rebase this properly?

@maki5 I tested you changes, looking good to me! 👍

We should enable this feature by default, i checked with @tbsbdr

That means we need to change the default config by setting this StructValue https://github.com/opencloud-eu/opencloud/blob/main/services/frontend/pkg/config/config.go#L62 in the defaultconfig.go to true