update workflow - auto assign yourself as assignee/reviewer

.codex/skills/implement-task/SKILL.md

@@ -23,6 +23,8 @@ description: Phase 2 skill. Use when issue scope is locked by Product Owner (Pha
    - Read issue: `mcp__gitea__.issue_read` (`method: "get"`).
    - Read comments, find the **Final Requirements** comment: `mcp__gitea__.issue_read` (`method: "get_comments"`).
    - If Final Requirements not found → stop, tell user to validate issue first.
+   - Read current Gitea user: `mcp__gitea__.get_me`.
+   - If current user is not already in the issue assignee list, update the issue with `mcp__gitea__.issue_write` (`method: "update"`) and set `assignees` to the existing assignees plus the current username.
 
 2. **Read codebase**
    - Use `mcp__gitea__.get_file_contents`, `mcp__gitea__.get_repository_tree` to understand current state.
@@ -72,6 +74,7 @@ description: Phase 2 skill. Use when issue scope is locked by Product Owner (Pha
 
 ## Rules
 - Use Gitea MCP tools for all issue/PR operations.
+- Preserve existing assignees when adding yourself unless the user explicitly asks to replace them.
 - Never edit remote files directly — always work on local branch.
 - Never claim completion without fresh verification output.
 - Keep changes strictly scoped to the approved plan.