fix: Skip quality checks in MCP context to prevent stdin errors

The MCP server's package_skill_tool was failing in CI because the quality
checker was prompting for user input, which doesn't exist in CI/MCP contexts.

Fix:
- Add --skip-quality-check flag to package_skill command in MCP server
- This prevents interactive prompts that cause EOFError in CI
- MCP tools should skip interactive checks since they run in background

Impact:
- All 25 MCP server tests now pass
- All 391 tests passing
- CI builds will succeed

Context:
- Quality checks are interactive by default for CLI users
- MCP server runs commands programmatically without user input
- This is the correct behavior: interactive for CLI, non-interactive for MCP

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/skill_seekers/mcp/server.py

@@ -676,7 +676,8 @@ async def package_skill_tool(args: dict) -> list[TextContent]:
         sys.executable,
         str(CLI_DIR / "package_skill.py"),
         skill_dir,
-        "--no-open"  # Don't open folder in MCP context
+        "--no-open",  # Don't open folder in MCP context
+        "--skip-quality-check"  # Skip interactive quality checks in MCP context
     ]
 
     # Add upload flag only if we have API key