Compiler-style diagnostics (--diag)

aiscope --diag .

Renders every conflict as a miette diagnostic with source spans — same look as cargo check.

Sample

× camelCase disagrees with snake_case
   ╭─[.github/copilot-instructions.md:5:1]
 4 │
 5 │ - Use **camelCase** for variables and functions.
   · ─────────────────────────────────────
 6 │
   ╰────
  help: the other side: .github/instructions/python.instructions.md:7:
        "Use snake_case for variables."

Why use it

• It's the format engineers already read — every Rust dev recognizes it.
• Source spans take you straight to the offending line.
• Works in PR comments — looks great pasted into GitHub markdown.

Combine with aiscope check

aiscope check --specific --diag .

Get diagnostic-style output and the non-zero exit code in one command — ideal for pre-commit and CI logs.