Do some performance optimize for issues list and view issue/pull (#29515)

This PR do some performance optimzations.

- [x] Add `index` for the column `comment_id` of `Attachment` table to
accelerate query from the database.
- [x] Remove unnecessary database queries when viewing issues. Before
some conditions which id = 0 will be sent to the database
- [x] Remove duplicated load posters 
- [x] Batch loading attachements, isread of comments on viewing issue

---------

Co-authored-by: Zettat123 <zettat123@gmail.com>

2 files changed, 16 insertions, 0 deletions

diff --git a/models/migrations/migrations.go b/models/migrations/migrations.go
index ce77432db4..87fddefb88 100644
--- a/models/migrations/migrations.go
+++ b/models/migrations/migrations.go
@@ -566,6 +566,8 @@ var migrations = []Migration{
 	NewMigration("Add default_wiki_branch to repository table", v1_22.AddDefaultWikiBranch),
 	// v290 -> v291
 	NewMigration("Add PayloadVersion to HookTask", v1_22.AddPayloadVersionToHookTaskTable),
+	// v291 -> v292
+	NewMigration("Add Index to attachment.comment_id", v1_22.AddCommentIDIndexofAttachment),
 }
 
 // GetCurrentDBVersion returns the current db version
diff --git a/models/migrations/v1_22/v291.go b/models/migrations/v1_22/v291.go
new file mode 100644
index 0000000000..0bfffe5d05
--- /dev/null
+++ b/models/migrations/v1_22/v291.go
@@ -0,0 +1,14 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_22 //nolint
+
+import "xorm.io/xorm"
+
+func AddCommentIDIndexofAttachment(x *xorm.Engine) error {
+	type Attachment struct {
+		CommentID int64 `xorm:"INDEX"`
+	}
+
+	return x.Sync(&Attachment{})
+}