Strings containing escapes resembling malformed UTF-8 crash the LSP

[evolbug]

Environment:

• Fedora Linux 44
• Zed 1.15.0 (Flatpak)
• Lua plugin 0.1.10
• LuaLS 3.19.1

Issue:

Interacting with strings containing escapes that appear like broken UTF-8, crashes the entire LSP. This includes interacting with variables containing those strings.

Replication:

1. Write the following code:

local fail = "\xC2"

2. Attempt to hover the string or reference the variable
3. Language server crashes with an UTF-8 parse error:

2026-08-14T22:28:31+02:00 ERROR [crates/lsp/src/lsp.rs:547] invalid utf-8 sequence of 1 bytes from index 113
2026-08-14T22:28:31+02:00 ERROR [lsp] Server reset connection for a request "textDocument/hover" id 18
2026-08-14T22:28:31+02:00 WARN  [project::lsp_store] Get hover via lua-language-server failed: Server reset the connection
2026-08-14T22:28:31+02:00 ERROR [project::lsp_store] Error handling response for request GetHover { position: PointUtf16 { row: 0, column: 14 } }: Get hover via lua-language-server failed: Server reset the connection
2026-08-14T22:28:32+02:00 WARN  [project::lsp_store] Get hover via lua-language-server failed: server shut down

4. The language server does not come back online.

Expected behaviour:

It should not crash on any kind of escaped sequence contained within string literals. If the sequence cannot be interpreted for display, it should be reported as-is or escaped bytewise, similar to what clangd does:

[notpeter]

I can reproduce on macOS.

// Send:
{"jsonrpc":"2.0","id":5,"method":"textDocument/hover","params":{"textDocument":{"uri":"file:///Users/peter/source/zed-lua/a.lua"},"position":{"line":0,"character":16}}}

2026-08-14T19:17:50-04:00 ERROR [crates/lsp/src/lsp.rs:563] invalid utf-8 sequence of 1 bytes from index 112
2026-08-14T19:17:50-04:00 ERROR [lsp] Server reset connection for a request "textDocument/hover" id 5
2026-08-14T19:17:50-04:00 WARN  [project::lsp_store] Get hover via lua-language-server failed: Server reset the connection
2026-08-14T19:17:50-04:00 ERROR [project::lsp_store] Error handling response for request GetHover { position: PointUtf16 { row: 0, column: 16 } }: Get hover via lua-language-server failed: Server reset the connection

There are two bugs here:

1. lua-language-server is sending JSON responses which include invalid UTF-8 data
   fix: more invalid UTF-8 JSON in hover/completions LuaLS/lua-language-server#3451
2. Zed should perhaps more gracefully handle/recovery receiving invalid data. This should probably be a distinct issue/discussion on the Zed repo. I'm not sure what the correct solution (try to recover? kill the LSP and restart? etc).