fix(cli): split IDE and shell profile checks in vp env doctor (#961)

## Summary

- Introduce tri-state `EnvSourcingStatus` (`IdeFound` / `ShellOnly` /
`NotFound`) to replace the boolean `check_ide_integration()` return
- Check IDE-visible profiles (`.zshenv`, `.profile`) first, then fall
back to all shell profiles (`.bashrc`, `.zshrc`, `.bash_profile`, fish
configs)
- Add proper fish shell support with `env.fish` pattern matching via
`is_fish` flag
- Parameterize `check_profile_files()` to accept profile list as
argument for reuse

This avoids the false positives that caused #878 to be rejected (marking
`.bashrc` as IDE-OK) while eliminating the false negatives from #881
(ignoring shell-only sourcing entirely).

Closes #881

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Co-authored-by: MK (fengmk2) <fengmk2@gmail.com>

Author: jong-kyung