findAllReferences inital port

[iisaduan]

This port focuses on the logic needed to resolving symbols within a single file.

Todos after this PR:

• Search for references through module resolving
• Search for references through imported and exported symbol resolving
  • Some imported and global symbols return references, but it is hard to test with the current lstestutil capabilities.
• Jsdoc references (not sure how much of the currently un-ported parts will be needed, since @sandersn has been working to simplify jsdoc checking)
• Special cases for object literals
• Special cases for classes and keywords
• String references

[Copilot]

Pull Request Overview

This PR ports the findAllReferences functionality and updates various components across the codebase. Key changes include:

• Adding new APIs and handlers (e.g. ResolveTripleslashReference in the path package and handleReferences in the LSP server) to support reference lookup.
• Replacing usage of older APIs (like GetAssignmentDeclarationKind) with new ones (GetJSDocAssignmentDeclarationKind) and renaming several utility functions for better export visibility.
• Introducing new testing files for findAllReferences and new core utilities (FlatMap and CoalesceList).

Reviewed Changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/tspath/path.go	Added ResolveTripleslashReference for triple-slash path resolution.
internal/parser/reparser.go	Updated assignment declaration kind calls to use GetJSDocAssignmentDeclarationKind.
internal/lsp/server.go	Added handling for ReferenceParams and a new handleReferences function.
internal/ls/findallreferencesexport_test.go	New test file for export reference lookups.
internal/ls/findallreferences_test.go	New tests covering various findAllReferences scenarios.
internal/core/core.go	Introduced FlatMap and CoalesceList utility functions.
internal/compiler/program.go	Added functions for module resolution improvements and extension handling.
internal/checker/utilities.go	Renamed internal helper functions (e.g. HasModifier, GetSingleVariableOfVariableStatement).
internal/checker/services.go	Added GetSymbolsOfParameterPropertyDeclaration for parameter-property handling.
internal/checker/printer.go	Updated modifier check call in expression printing.
internal/checker/exports.go	Added exported helper functions for type operations and symbol merging.
internal/checker/checker.go	Replaced legacy modifier and assignment kind calls with their updated versions.
internal/binder/nameresolver.go	Updated internal module/enum checks and exported GetLocalSymbolForExportDefault.
internal/binder/binder.go	Switched to use GetJSDocAssignmentDeclarationKind in assignment binding logic.
internal/astnav/tokens.go	Added GetTouchingToken as an alternative for token retrieval in AST.
internal/ast/utilities.go	Introduced several new AST helper functions and renamed utility methods.

[sandersn]

I haven't read findallreferences.go yet but here are my comments for the rest. I focussed on changes needed for JS. I'll follow up with comments for the big file tomorrow.

[sandersn]

Minor comments on findallreferences.go, nothing substantive.

[jakebailey]

Seems like this fails to compile, probably due to more code getting added in other PRs.