feat(node): enable logging and show full errors (#1775)

This exposes the `LANCEDB_LOG` environment variable in node, so that
users can now turn on logging.

In addition, fixes a bug where only the top-level error from Rust was
being shown. This PR makes sure the full error chain is included in the
error message. In the future, will improve this so the error chain is
set on the [cause](https://nodejs.org/api/errors.html#errorcause)
property of JS errors https://github.com/lancedb/lancedb/issues/1779

Fixes #1774

docs/mkdocs.yml

@@ -211,9 +211,10 @@ nav:
               - TransformersJS Embedding Search: examples/transformerjs_embedding_search_nodejs.md
           - 🦀 Rust:
               - Overview: examples/examples_rust.md
-      - Studies:
+      - 📓 Studies:
           - ↗Improve retrievers with hybrid search and reranking: https://blog.lancedb.com/hybrid-search-and-reranking-report/
       - 💭 FAQs: faq.md
+      - 🔍 Troubleshooting: troubleshooting.md
       - ⚙️ API reference:
           - 🐍 Python: python/python.md
           - 👾 JavaScript (vectordb): javascript/modules.md

docs/src/troubleshooting.md

@@ -0,0 +1,33 @@
+## Getting help
+
+The following sections provide various diagnostics and troubleshooting tips for LanceDB.
+These can help you provide additional information when asking questions or making
+error reports.
+
+For trouble shooting, the best place to ask is in our Discord, under the relevant
+language channel. By asking in the language-specific channel, it makes it more
+likely that someone who knows the answer will see your question.
+
+## Enabling logging
+
+To provide more information, especially for LanceDB Cloud related issues, enable
+debug logging. You can set the `LANCEDB_LOG` environment variable:
+
+```shell
+export LANCEDB_LOG=debug
+```
+
+You can turn off colors and formatting in the logs by setting
+
+```shell
+export LANCEDB_LOG_STYLE=never
+```
+
+## Explaining query plans
+
+If you have slow queries or unexpected query results, it can be helpful to
+print the resolved query plan. You can use the `explain_plan` method to do this:
+
+* Python Sync: [LanceQueryBuilder.explain_plan][lancedb.query.LanceQueryBuilder.explain_plan]
+* Python Async: [AsyncQueryBase.explain_plan][lancedb.query.AsyncQueryBase.explain_plan]
+* Node @lancedb/lancedb: [LanceQueryBuilder.explainPlan](/lancedb/js/classes/QueryBase/#explainplan)