Runaway memory usage (100GB+) during burst multi-file edits (AI agent runs in Zed)

### Environment
- OS: macOS
- Editor: Zed
- Server: Expert LSP

### Description
When editing many Elixir files in a short time (for example during an AI agent run in Zed), the `beam.smp` process memory grows without reclaiming space. I saw it exceed 100GB before having to kill it.

### Steps to reproduce
1. Open an Elixir project in Zed with Expert enabled.
2. Run an AI agent on a task that touches or edits multiple files across the codebase.
3. Watch `beam.smp` in Activity Monitor as the agent hops between files. Memory quickly climbs into the tens/hundreds of gigabytes and is not freed.

### Expected behavior
Memory should stay bounded when multiple file change events arrive in quick succession.

### Workaround
Kill the `beam.smp` process in Activity Monitor.