Shipwright: verify Zed extension reads shipwright.json + checks expectedVersion

Problem

basilisk-zed/src/lib.rs downloads the latest GitHub release and tracks cached_binary_version, but never reads shipwright.json (or deployment-toolkit.json) to learn the expected version, and never verifies the running server's version against an expected value from the manifest.

```rust
// src/lib.rs
let (path, version) = Self::download_binary()?;
self.cached_binary_version = Some(version);
// ...later:
if logic::is_newer_version(current, &latest_release.version) { /* warn */ }
```

Per [SWR-VERSION-LSP], IDE hosts must verify the LSP server's version (from InitializeResult.serverInfo.version) against the expectedVersion declared in shipwright.json. Per [SWR-IDE-ERROR], mismatches must be surfaced with expected, found, and path.

Spec citations

• [SWR-VERSION-LSP] — verify server version from initialize metadata
• [SWR-IDE-ERROR] — error surface for mismatches
• [SWR-VERSION-CONTRACT] — manifest is the source of truth for expected version

Spec references

The Shipwright deployment specs are at https://github.com/Nimblesite/Shipwright (private repo). Use Playwright (mcp__playwright__browser_navigate) in an authenticated browser to view them.

• https://github.com/Nimblesite/Shipwright/blob/package-deployment/docs/specs/binary-version-contract.md
• https://github.com/Nimblesite/Shipwright/blob/package-deployment/docs/specs/ide-extension-deployment.md

Acceptance criteria

• Zed extension parses shipwright.json (after rename — see manifest-rename issue) on startup
• Reads expectedVersion for the basilisk component (resolves ${PRODUCT_VERSION})
• Compares against InitializeResult.serverInfo.version after LSP initialize
• On mismatch with hosts.zed.onMismatch: error, surfaces a notification with expected, found, and binary path; refuses to use the server
• Existing is_newer_version GitHub-release check kept as a separate informational warning

Start in basilisk-zed/src/lib.rs, then review the referenced Shipwright version-contract and IDE-extension specs in an authenticated browser with Playwright. Trace startup, binary download, and LSP initialization, keeping the existing is_newer_version warning separate. Done means the acceptance criteria are met, including the expected, found, and binary path notification on mismatch.