The dist-side bug reported in #4220 (`path.endsWith(\"dist/cli.js\")` failing on
Windows backslash paths) has already been fixed in source by routing through
`hasCliSuffix` in `src/mcp/ast-grep.ts` and `src/mcp/lsp.ts`. The `cli-suffix.test.ts`
covered the lsp-tools-mcp shape but not the ast_grep shape.
Adds a regression case that asserts a Windows-style absolute path containing
`...\\packages\\ast-grep-mcp\\dist\\cli.js` matches both `\"dist/cli.js\"` and the
fully-qualified `\"packages/ast-grep-mcp/dist/cli.js\"` suffix — closing the
exact symptom from the bug report against future regressions.
On Windows, path.resolve() returns paths with backslash separators. The previous endsWith("dist/cli.js") check uses forward slashes and always returned false on Windows, causing both LSP and ast-grep MCPs to fall through to the bootstrap path even when the dist cli exists. Result: LSP MCP completely unusable on Windows with MODULE_NOT_FOUND for dist/packages/lsp-tools-mcp/dist/cli.js.
Fix: derive a platform-aware suffix at module load time by replacing forward slashes in DIST_CLI_REL / SOURCE_CLI_REL with path.sep, then use that suffix in the endsWith check.
Verification: all 4 src/mcp/lsp.test.ts cases pass on Windows (previously 2 failed); all 13 src/mcp/ast-grep.test.ts cases pass (previously 2 failed). Total: 17/17 src/mcp tests green. bun run typecheck clean.
李冠辰