perf: improve Java LSP tool result handoff

[wenytang-ms]

Summary

This draft follows the 0.27.5 Java LSP telemetry diagnosis:

• findSymbol -> findSymbol improved from the 0.27.4 baseline but is still high (~43.8%).
• For success_small_result, the next tool is still findSymbol ~41.7% of the time, even though these results should usually be directly consumable.
• getFileStructure still has a noticeable fileNotFound / outsideWorkspace tail, and findSymbol previously returned location as path:line while getFileStructure expected a clean path.

Changes

• Return more directly consumable findSymbol result fields: file, startLine, endLine, range, and outlineInput.
• Add a top-level nextStep hint to findSymbol responses, with stronger guidance for small exact result sets.
• Let file resolution tolerate Java location strings such as src/Foo.java:42.
• Improve multi-root relative-path handling when asRelativePath includes the workspace folder name.
• Update LM tool metadata, skill docs, and Java chat instruction to prefer outlineInput / file handoff.

Validation

• npm run compile
• npm run tslint
• npm test currently fails in existing Library Controller tests because toReferencedLibraryPath / toReferencedLibraryExcludePath are not exported from extension_bundle_1; unrelated to this LSP tool change.

[Copilot]

Pull request overview

This PR improves the Java LSP Copilot tools’ result “handoff” so downstream steps (e.g., read_file / lsp_java_getFileStructure) can consume lsp_java_findSymbol output more directly, and so file resolution is more tolerant of Java-style path:line inputs and multi-root workspaces.

Changes:

• Enhanced lsp_java_findSymbol payload with file, startLine, endLine, and outlineInput, and added a nextStep hint to reduce unnecessary repeat tool calls.
• Made file URI resolution tolerate Java location suffixes (e.g., src/Foo.java:42) and improved multi-root relative-path handling when the workspace folder name is included.
• Updated skill docs, instrument instructions, and tool metadata to prefer outlineInput/file handoff patterns.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/copilot/tools/javaContextTools.ts	Adds Java path:line tolerance, improves multi-root relative resolution, and enriches findSymbol results with additional fields and guidance.
resources/skills/java-lsp-tools/SKILL.md	Documents the updated findSymbol output fields and the preferred handoff flow using outlineInput/file.
resources/instruments/javaLspContext.instructions.md	Updates Java chat instructions to prefer read_file with file/range and getFileStructure with outlineInput.
package.json	Updates tool metadata/schema descriptions to reflect new fields and tolerated path:line inputs.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.