chore(llma): bump @langchain/core from 1.1.17 to 1.1.27 in the ai-providers group (#3137)

* chore(llma): bump @langchain/core in the ai-providers group

Bumps the ai-providers group with 1 update: [@langchain/core](https://github.com/langchain-ai/langchainjs).


Updates `@langchain/core` from 1.1.17 to 1.1.27
- [Release notes](https://github.com/langchain-ai/langchainjs/releases)
- [Commits](https://github.com/langchain-ai/langchainjs/commits)

---
updated-dependencies:
- dependency-name: "@langchain/core"
  dependency-version: 1.1.27
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: ai-providers
...

Signed-off-by: dependabot[bot] <support@github.com>

* chore(dependencies): updated changesets for modified dependencies

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
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Author: dependabot[bot]

.changeset/@posthog_ai-3137-dependencies.md

@@ -0,0 +1,5 @@
+---
+'@posthog/ai': patch
+---
+dependencies updates:
+    - Updated dependency [`@langchain/core@^1.1.27` ↗︎](https://www.npmjs.com/package/@langchain/core/v/1.1.27) (from `^1.1.17`, in `dependencies`)

packages/ai/package.json

@@ -49,7 +49,7 @@
   "dependencies": {
     "@anthropic-ai/sdk": "^0.78.0",
     "@google/genai": "^1.42.0",
-    "@langchain/core": "^1.1.17",
+    "@langchain/core": "^1.1.27",
     "@posthog/core": "workspace:*",
     "langchain": "^1.2.25",
     "openai": "^6.22.0",