Enum CacheEffect 

pub enum CacheEffect {
    None,
    Invalidate,
    StoreFull(String),
}

A cache mutation that an edit needs after its disk I/O completes.

Decoupling the cache mutation from the I/O lets the MCP layer perform the (slow) file read/replace/write while holding only a cheap per-file lock, then touch the shared cache for a sub-millisecond instant — instead of holding the global cache write-lock across all disk I/O (the root cause of issue #320).

Variants

None

No cache change required (e.g. the edit failed before writing).

Invalidate

The file on disk changed; drop the stale cache entry.

StoreFull(String)

Auto-escalation re-read full content that should be stored and marked as fully delivered.