feat: prompt file searching

[LOTaher]

Added file fuzzy searching within the prompt window. Significant changes to note:

• Created a new path module that contains all path related functions. I moved a few from tags as it seemed like a better fit in path. Feel free to push back on this.
• If the cwd is not a git project, then parse all available files (currently, even from directories like node_modules) and show them in the cmp completion window.
  • I did not change how the completion buffer can be navigated, so navigate using arrow keys and pressing enter.
• Separated @ lsp detection entirely when parsing the @.

Screen.Recording.2026-05-23.at.3.23.38.AM.mov

refs:

completes #20, which is (kinda) needed for #19

[cachebag]

LGTM