Improve compatibility with kotlin.nvim

[PEMessage]

Problem Statement

kotlin.nvim (https://github.com/AlexandrosAlexiou/kotlin.nvim) also registers BufReadCmd for jar:// and jrt:// (reference) URIs to decompile class files: something like

jar:///path/to/home/.gradle/caches/9.4.1/transforms/77d3e221d79acc53b2b96474454cadc6/transformed/activity-1.7.2/j
ars/classes.jar!/androidx/activity/ComponentActivity.class

When LSP tagfunc triggers a buffer load with a jar:// URI, open_classfile unconditionally passes it through vim.uri_from_fname(), corrupting the URI. and assert trigger

nvim-jdtls/lua/jdtls.lua

Line 1255 in 6e9d953

assert(client, 'Must have a `jdtls` client to load class file or jdt uri')

Ideas or possible solutions

Checking if fname already a uri

PEMessage@1c3db36