docs(tools/spxls): add README.md

Updates #1059

Signed-off-by: Aofei Sheng <[email protected]>

tools/spxls/README.md

@@ -0,0 +1,42 @@
+# spxls
+
+A lightweight Go+ language server for [spx](https://github.com/goplus/spx) that runs in the browser using WebAssembly.
+
+## LSP methods
+
+| Category | Method | Purpose & Explanation |
+|----------|--------|-----------------------|
+| **Lifecycle Management** |||
+|| [`initialize`](https://microsoft.github.io/language-server-protocol/specifications/base/0.9/specification/#initialize) | Performs initial handshake, establishes server capabilities and client configuration. |
+|| [`initialized`](https://microsoft.github.io/language-server-protocol/specifications/base/0.9/specification/#initialized) | Marks completion of initialization process, enabling request processing. |
+|| [`shutdown`](https://microsoft.github.io/language-server-protocol/specifications/base/0.9/specification/#shutdown) | *Protocol conformance only.* |
+|| [`exit`](https://microsoft.github.io/language-server-protocol/specifications/base/0.9/specification/#exit) | *Protocol conformance only.* |
+| **Document Synchronization** |||
+|| [`textDocument/didOpen`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_didOpen) | Registers new document in server state and triggers initial diagnostics. |
+|| [`textDocument/didChange`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_didChange) | Synchronizes document content changes between client and server. |
+|| [`textDocument/didSave`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_didSave) | Processes document save events and triggers related operations. |
+|| [`textDocument/didClose`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_didClose) | Removes document from server state and cleans up resources. |
+| **Code Intelligence** |||
+|| [`textDocument/hover`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_hover) | Shows types and documentation at cursor position. |
+|| [`textDocument/completion`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_completion) | Generates context-aware code suggestions. |
+|| [`completionItem/resolve`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#completionItem_resolve) | Provides detailed information for selected completion items. |
+|| [`textDocument/signatureHelp`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_signatureHelp) | Shows function/method signature information. |
+|| [`textDocument/inlayHint`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_inlayHint) | Provides inline hints (type information, parameter names). |
+| **Symbols & Navigation** |||
+|| [`textDocument/definition`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_definition) | Locates symbol definitions across codebase. |
+|| [`textDocument/declaration`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_declaration) | Finds symbol declarations. |
+|| [`textDocument/typeDefinition`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_typeDefinition) | Navigates to type definitions of variables/fields. |
+|| [`textDocument/implementation`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_implementation) | Locates implementations. |
+|| [`textDocument/references`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_references) | Finds all references of a symbol. |
+|| [`textDocument/documentSymbol`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_documentSymbol) | Provides document symbols for outline/navigation. |
+|| [`textDocument/documentHighlight`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_documentHighlight) | Highlights other occurrences of selected symbol. |
+| **Code Quality** |||
+|| [`textDocument/publishDiagnostics`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_publishDiagnostics) | Reports code errors and warnings in real-time. |
+|| [`textDocument/codeAction`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_codeAction) | Suggests fixes for diagnostics and code improvements. |
+| **Code Modification** |||
+|| [`textDocument/formatting`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_formatting) | Applies standardized formatting rules to document. |
+|| [`textDocument/rename`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_rename) | Performs consistent symbol renaming across codebase. |
+| **Semantic Features** |||
+|| [`textDocument/semanticTokens/full`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#semanticTokens_fullRequest) | Provides semantic coloring for whole document. |
+
+## [TBD]