Add user blocking (#29028)

Fixes #17453

This PR adds the abbility to block a user from a personal account or
organization to restrict how the blocked user can interact with the
blocker. The docs explain what's the consequence of blocking a user.

Screenshots:


![grafik](https://github.com/go-gitea/gitea/assets/1666336/4ed884f3-e06a-4862-afd3-3b8aa2488dc6)


![grafik](https://github.com/go-gitea/gitea/assets/1666336/ae6d4981-f252-4f50-a429-04f0f9f1cdf1)


![grafik](https://github.com/go-gitea/gitea/assets/1666336/ca153599-5b0f-4b4a-90fe-18bdfd6f0b6b)

---------

Co-authored-by: Lauris BH <lauris@nix.lv>

options/locale/locale_en-US.ini

@@ -632,6 +632,30 @@ form.name_reserved = The username "%s" is reserved.
 form.name_pattern_not_allowed = The pattern "%s" is not allowed in a username.
 form.name_chars_not_allowed = User name "%s" contains invalid characters.
 
+block.block = Block
+block.block.user = Block user
+block.block.org = Block user for organization
+block.block.failure = Failed to block user: %s
+block.unblock = Unblock
+block.unblock.failure = Failed to unblock user: %s
+block.blocked = You have blocked this user.
+block.title = Block a user
+block.info = Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.
+block.info_1 = Blocking a user prevents the following actions on your account and your repositories:
+block.info_2 = following your account
+block.info_3 = send you notifications by @mentioning your username
+block.info_4 = inviting you as a collaborator to their repositories
+block.info_5 = starring, forking or watching on repositories
+block.info_6 = opening and commenting on issues or pull requests
+block.info_7 = reacting on your comments in issues or pull requests
+block.user_to_block = User to block
+block.note = Note
+block.note.title = Optional note:
+block.note.info = The note is not visible to the blocked user.
+block.note.edit = Edit note
+block.list = Blocked users
+block.list.none = You have not blocked any users. 
+
 [settings]
 profile = Profile
 account = Account
@@ -969,6 +993,7 @@ fork_visibility_helper = The visibility of a forked repository cannot be changed
 fork_branch = Branch to be cloned to the fork
 all_branches = All branches
 fork_no_valid_owners = This repository can not be forked because there are no valid owners.
+fork.blocked_user = Cannot fork the repository because you are blocked by the repository owner.
 use_template = Use this template
 open_with_editor = Open with %s
 download_zip = Download ZIP
@@ -1144,6 +1169,7 @@ watch = Watch
 unstar = Unstar
 star = Star
 fork = Fork
+action.blocked_user = Cannot perform action because you are blocked by the repository owner.
 download_archive = Download Repository
 more_operations = More Operations
 
@@ -1394,6 +1420,8 @@ issues.new.assignees = Assignees
 issues.new.clear_assignees = Clear assignees
 issues.new.no_assignees = No Assignees
 issues.new.no_reviewers = No reviewers
+issues.new.blocked_user = Cannot create issue because you are blocked by the repository owner.
+issues.edit.blocked_user = Cannot edit content because you are blocked by the poster or repository owner.
 issues.choose.get_started = Get Started
 issues.choose.open_external_link = Open
 issues.choose.blank = Default
@@ -1509,6 +1537,7 @@ issues.close_comment_issue = Comment and Close
 issues.reopen_issue = Reopen
 issues.reopen_comment_issue = Comment and Reopen
 issues.create_comment = Comment
+issues.comment.blocked_user = Cannot create or edit comment because you are blocked by the poster or repository owner.
 issues.closed_at = `closed this issue <a id="%[1]s" href="#%[1]s">%[2]s</a>`
 issues.reopened_at = `reopened this issue <a id="%[1]s" href="#%[1]s">%[2]s</a>`
 issues.commit_ref_at = `referenced this issue from a commit <a id="%[1]s" href="#%[1]s">%[2]s</a>`
@@ -1707,6 +1736,7 @@ compare.compare_head = compare
 
 pulls.desc = Enable pull requests and code reviews.
 pulls.new = New Pull Request
+pulls.new.blocked_user = Cannot create pull request because you are blocked by the repository owner.
 pulls.view = View Pull Request
 pulls.compare_changes = New Pull Request
 pulls.allow_edits_from_maintainers = Allow edits from maintainers
@@ -2120,6 +2150,7 @@ settings.convert_fork_succeed = The fork has been converted into a regular repos
 settings.transfer = Transfer Ownership
 settings.transfer.rejected = Repository transfer was rejected.
 settings.transfer.success = Repository transfer was successful.
+settings.transfer.blocked_user = Cannot transfer repository because you are blocked by the new owner.
 settings.transfer_abort = Cancel transfer
 settings.transfer_abort_invalid = You cannot cancel a non existent repository transfer.
 settings.transfer_abort_success = The repository transfer to %s was successfully canceled.
@@ -2165,6 +2196,7 @@ settings.add_collaborator_success = The collaborator has been added.
 settings.add_collaborator_inactive_user = Cannot add an inactive user as a collaborator.
 settings.add_collaborator_owner = Cannot add an owner as a collaborator.
 settings.add_collaborator_duplicate = The collaborator is already added to this repository.
+settings.add_collaborator.blocked_user = The collaborator is blocked by the repository owner or vice versa.
 settings.delete_collaborator = Remove
 settings.collaborator_deletion = Remove Collaborator
 settings.collaborator_deletion_desc = Removing a collaborator will revoke their access to this repository. Continue?
@@ -2731,6 +2763,7 @@ teams.add_nonexistent_repo = "The repository you're trying to add doesn't exist,
 teams.add_duplicate_users = User is already a team member.
 teams.repos.none = No repositories could be accessed by this team.
 teams.members.none = No members on this team.
+teams.members.blocked_user = Cannot add the user because it is blocked by the organization.
 teams.specific_repositories = Specific repositories
 teams.specific_repositories_helper = Members will only have access to repositories explicitly added to the team. Selecting this <strong>will not</strong> automatically remove repositories already added with <i>All repositories</i>.
 teams.all_repositories = All repositories