feat(service): expand service layer with new domain operations

- Add IM service modules: audit, channel roles, custom emojis, forum
  tags, integrations, invitations, repo links, slash commands, stages,
  voice, webhooks
- Add PR service modules: review requests, templates
- Add repo service modules: contributors, release assets, git extras
  (archive, branch rename, commit extras, diff/merge, tag, tree)
- Add user service: social (follow/block)
- Add internal auth service
- Update existing service modules with expanded functionality
- Remove deleted IM modules: articles, delivery trace, drafts,
  follows, messages, polls, presence, reactions, threads

service/wiki/core.rs

@@ -6,7 +6,7 @@ use crate::models::wiki::WikiPage;
 use crate::service::RepoService;
 use crate::session::Session;
 
-use super::util::{clamp_limit_offset, ensure_affected, required_text};
+use super::util::{clamp_limit_offset, ensure_affected, required_text, set_local_user_id};
 
 #[derive(serde::Deserialize, serde::Serialize, Clone, Debug, utoipa::ToSchema)]
 pub struct CreateWikiPageParams {
@@ -120,8 +120,7 @@ impl RepoService {
             .begin()
             .await
             .map_err(|_| AppError::TxnError)?;
-        sqlx::query("SET LOCAL app.current_user_id = $1")
-            .bind(user_uid)
+        sqlx::query(set_local_user_id(user_uid))
             .execute(&mut *txn)
             .await
             .map_err(AppError::Database)?;
@@ -190,15 +189,14 @@ impl RepoService {
             .begin()
             .await
             .map_err(|_| AppError::TxnError)?;
-        sqlx::query("SET LOCAL app.current_user_id = $1")
-            .bind(user_uid)
+        sqlx::query(set_local_user_id(user_uid))
             .execute(&mut *txn)
             .await
             .map_err(AppError::Database)?;
 
         let updated = sqlx::query_as::<_, WikiPage>(
             "UPDATE wiki_page SET title = $1, content = $2, last_editor_id = $3, version = $4, updated_at = $5 \
-             WHERE id = $6 AND deleted_at IS NULL \
+             WHERE id = $6 AND deleted_at IS NULL AND version = $7 \
              RETURNING id, repo_id, slug, title, content, author_id, last_editor_id, version, created_at, updated_at, deleted_at",
         )
         .bind(&new_title)
@@ -207,9 +205,11 @@ impl RepoService {
         .bind(new_version)
         .bind(now)
         .bind(page.id)
-        .fetch_one(&mut *txn)
+        .bind(page.version)
+        .fetch_optional(&mut *txn)
         .await
-        .map_err(AppError::Database)?;
+        .map_err(AppError::Database)?
+        .ok_or(AppError::Conflict("page was modified concurrently; please refresh and try again".into()))?;
 
         sqlx::query(
             "INSERT INTO wiki_page_revision (id, page_id, version, title, content, editor_id, commit_message, created_at) \
@@ -305,15 +305,28 @@ impl RepoService {
     }
 
     fn generate_slug(title: &str) -> String {
-        title
+        let slug: String = title
             .to_lowercase()
             .chars()
-            .map(|c| if c.is_alphanumeric() { c } else { '-' })
+            .map(|c| {
+                if c.is_alphanumeric() || c.is_ascii_alphanumeric() {
+                    c
+                } else {
+                    '-'
+                }
+            })
             .collect::<String>()
             .split('-')
             .filter(|s| !s.is_empty())
             .collect::<Vec<_>>()
-            .join("-")
+            .join("-");
+
+        // If slug is empty (e.g., all non-ASCII characters), generate a fallback
+        if slug.is_empty() {
+            format!("page-{}", uuid::Uuid::now_v7().as_simple())
+        } else {
+            slug
+        }
     }
 
     async fn generate_wiki_slug(&self, repo_id: Uuid, title: &str) -> Result<String, AppError> {