AtomicServer Files

Security patch release for the 0.40 line. Both fixes concern the WASM plugin installer, which is built by default (wasm-plugins is in the default feature set) and reachable by any agent with ordinary write access to a Drive — no admin rights required.

• Reject path traversal in plugin zip asset entries. A zip entry named assets/../../.. was joined onto the plugin directory using the raw, attacker-controlled entry name, allowing arbitrary file write with attacker-controlled content anywhere the server process could write (GHSA-g2q9-fjm7-cmm3). Entry names under assets/ must now be plain relative paths of normal components. Reported by @T4ran24.
• Reject path traversal in plugin namespace/name on uninstall. Both values were read straight off the Plugin resource and joined into filesystem paths, so a ../ payload could delete arbitrary files or recursively delete a directory (GHSA-vr56-vwrw-w2vg). Both are now validated as a single path segment on every path that reaches the filesystem, with a direct-child check as defense in depth.

Version bumps: atomic_lib 0.40.1 -> 0.40.2, atomic-server 0.40.3 -> 0.40.4 (cli untouched). server's atomic_lib dep pinned to 0.40.2.