Bump langchain from 0.0.84 to 0.2.19

Bumps [langchain](https://github.com/langchain-ai/langchainjs) from 0.0.84 to 0.2.19.
- [Release notes](https://github.com/langchain-ai/langchainjs/releases)
- [Changelog](https://github.com/langchain-ai/langchainjs/blob/main/release_workspace.js)
- [Commits](langchain-ai/langchainjs@0.0.84...0.2.19)

---
updated-dependencies:
- dependency-name: langchain
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package.json

@@ -32,7 +32,7 @@
     "better-sqlite3": "11.5.0",
     "discord.js": "^14.16.1",
     "fs": "0.0.1-security",
-    "langchain": "^0.0.84",
+    "langchain": "^0.2.19",
     "net": "1.0.2",
     "openai": "^4.83.0",
     "path": "0.12.7",