Show if commit is signed in activity feed and unify sha box (#6933)

Old activities are shown like before, new commits are displayed like commits in e.g. the commits list. _(Second commit)_

| New signed commits | Old (signed) commits |
|:--:|:--:|
| ![image](/attachments/cd81c761-eda6-44bf-8c43-ac3b7e6f16eb) | ![image](/attachments/243080f3-1b77-4ca7-bc03-bbf855c39c99) |

Additionally the sha box was moved in an own component to unify the usage. _(First commit)_

Closes #1824

<!--start release-notes-assistant-->

## Release notes
<!--URL:https://codeberg.org/forgejo/forgejo-->
- User Interface features
  - [PR](https://codeberg.org/forgejo/forgejo/pulls/6933): <!--number 6933 --><!--line 0 --><!--description U2hvdyBpZiBjb21taXQgaXMgdmVyaWZpZWQgaW4gYWN0aXZpdHkgZmVlZCBvZiBhbiB1c2VyIG9yIGFuIG9yZ2FuaXphdGlvbiBmb3IgbmV3IGFjdGl2aXR5-->Show if commit is verified in activity feed of an user or an organization for new activity<!--description-->
<!--end release-notes-assistant-->

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/6933
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Beowulf <beowulf@beocode.eu>
Co-committed-by: Beowulf <beowulf@beocode.eu>

modules/repository/commits.go

@@ -1,4 +1,5 @@
 // Copyright 2019 The Gitea Authors. All rights reserved.
+// Copyright 2025 The Forgejo Authors. All rights reserved.
 // SPDX-License-Identifier: MIT
 
 package repository
@@ -9,6 +10,7 @@ import (
 	"net/url"
 	"time"
 
+	asymkey_model "forgejo.org/models/asymkey"
 	"forgejo.org/models/avatars"
 	user_model "forgejo.org/models/user"
 	"forgejo.org/modules/cache"
@@ -26,6 +28,8 @@ type PushCommit struct {
 	AuthorName     string
 	CommitterEmail string
 	CommitterName  string
+	Signature      *git.ObjectSignature
+	Verification   *asymkey_model.ObjectVerification
 	Timestamp      time.Time
 }
 
@@ -145,6 +149,32 @@ func (pc *PushCommits) AvatarLink(ctx context.Context, email string) string {
 	return v
 }
 
+// PushCommitToCommit transforms a PushCommit to a git.Commit type on a best effort basis.
+//
+// Attention: Converting a Commit to a PushCommit and converting back to a Commit will not result in an identical object!
+func PushCommitToCommit(commit *PushCommit) (*git.Commit, error) {
+	id, err := git.NewIDFromString(commit.Sha1)
+	if err != nil {
+		return nil, err
+	}
+	return &git.Commit{
+		ID: id,
+		Author: &git.Signature{
+			Name:  commit.AuthorName,
+			Email: commit.AuthorEmail,
+			When:  commit.Timestamp,
+		},
+		Committer: &git.Signature{
+			Name:  commit.CommitterName,
+			Email: commit.CommitterEmail,
+			When:  commit.Timestamp,
+		},
+		CommitMessage: commit.Message,
+		Signature:     commit.Signature,
+		Parents:       []git.ObjectID{},
+	}, nil
+}
+
 // CommitToPushCommit transforms a git.Commit to PushCommit type.
 func CommitToPushCommit(commit *git.Commit) *PushCommit {
 	return &PushCommit{
@@ -154,6 +184,7 @@ func CommitToPushCommit(commit *git.Commit) *PushCommit {
 		AuthorName:     commit.Author.Name,
 		CommitterEmail: commit.Committer.Email,
 		CommitterName:  commit.Committer.Name,
+		Signature:      commit.Signature,
 		Timestamp:      commit.Author.When,
 	}
 }