regression: erratic behavior with selected lines

[dustinfarris]

I'm not sure if this is a regression of #15 or something else.

I recorded a video demonstrating:

1. Highlighting 1 line with evil V
   not indicated in Claude, just shows "in file test.md"
   when asked, Claude is not aware of any line being highlighted
2. Highlighting 2 lines with evil V k
   indicated as "1 line selected"
   however when asked, Claude is not aware of any line being highlighted.
3. Highlighting 2 lines with evil V j
   is indicated as "1 line selected"
   when asked, Claude is aware of the first of the two lines.
4. Highlighting 3 lines with evil V j j
   indicated as "2 lines selected"
   when asked, Claude is aware of the first 2 of the 3 lines.

Screen.Recording.2026-02-20.at.8.14.35.AM.720p.mov