fix(search): resolve hlslens integration with module caching

[kanghyki]

Problem

The hlslens search handler was not working when hlslens was loaded before
nvim-scrollbar due to Lua's module caching mechanism.

Root Cause

1. When hlslens loads first, it calls require('hlslens.config') which runs
   the init() function and caches the config with build_position_cb = nil
2. Later when search.setup() calls hlslens.setup() with the callback,
   hlslens stores it in hlslens._config but the cached config module is never updated
3. The init() function only runs once when the module is first required,
   so subsequent hlslens.setup() calls don't update the cached config

Reproduction

With this plugin loading order:

require('hlslens').setup()  -- Loads first, caches config with nil callback
require('scrollbar.handlers.search').setup()  -- Config already cached

Result: Search marks don't appear on scrollbar

Solution

Directly modify the cached hlslens.config object instead of calling hlslens.setup().
Since Lua tables are passed by reference, modifying the cached config object updates it everywhere.

Note: Alternatively, users can avoid this issue by removing require('hlslens').setup() from their configuration and letting nvim-scrollbar handle hlslens initialization.

Changes

• Remove hlslens.setup() call
• Directly access hlslens.config via require("hlslens.config")
• Set build_position_cb directly on the config object

Benefits

• Works regardless of plugin loading order
• Preserves all existing hlslens configuration

Environment

• OS: macOS (Darwin 25.0.0)
• Neovim: NVIM v0.11.4
• Plugin Manager: vim-plug

#83

[petertriho]

Thanks @kanghyki

This probably resolves a few issues others have seen with the hlslens integration