next_lint detector silently reports zero issues on Next.js 16 (`next lint` was removed)

[miguelalfredooo]

Problem

NEXTJS_SPEC hardcodes the lint command:

# desloppify/languages/_framework/frameworks/specs/nextjs.py:547
cmd="npx --no-install next lint --format json",

Next.js 16 removed the lint subcommand. The invocation is now parsed as next <dir>, so it exits with:

$ npx next lint
Invalid project directory provided, no such directory: /path/to/project/lint

This does not fail loudly. The scan records reduced coverage:

Coverage reduced (next_lint): next lint tooling unavailable (parser_error)

…and reports zero lint issues. A Next 16 codebase reads as lint-clean when it is not. On the project I hit this on, eslint reports 6 real warnings across 5 files that next_lint contributed nothing about.

Repro

Any project with next@>=16 installed:

desloppify scan --path .
# → "Coverage reduced (next_lint): next lint tooling unavailable (parser_error)"

Environment: desloppify 1.0, next 16.3.0, Python 3.14.3, macOS.

Suggested fix

Resolve the command from the installed Next.js major (read node_modules/next/package.json, not the declared range — ^15.0.0 can resolve to 16) and run ESLint directly on >=16. Convenient detail: eslint --format json emits exactly the [{filePath, messages}] shape parse_next_lint already parses, so the parser needs no change.

To keep this general, I added an optional ToolIntegration.cmd_resolver: Callable[[Path], str | None] resolved per scan root in _framework_tool_phase. When it is absent or returns None, behaviour is unchanged — so projects on Next <=15, or with nothing installed to inspect, keep the historical command.

Patch

I have a working, tested branch. Diff summary:

 .../frameworks/phases.py                          | 34 ++++++---
 .../frameworks/specs/nextjs.py                    | 46 +++++++++++-
 .../frameworks/types.py                           |  6 ++
 .../typescript/tests/test_ts_nextjs_framework.py  | 75 ++++++++++++++++++++
 4 files changed, 149 insertions(+), 12 deletions(-)

8 new tests cover: the version→command mapping across majors 14/15/16/17, v-prefixed versions, unreadable/absent package.json falling back to None, the spec actually declaring the resolver, and a behavioral test asserting the resolved command reaches the tool runner (verified to fail against pre-fix code, not just pass against post-fix).

Full suite: 6757 passed. Four failures exist on main before this change and are unrelated (test_ts_nextjs_framework is not among them):

• desloppify/languages/ruby/tests/test_init.py::test_has_required_phases[Coupling + cycles + orphaned]
• 3 in desloppify/tests/lang/common/test_bash_unused_imports.py

I could not push a branch (no write access to this repo). Happy to open a PR from a fork if that is useful — just say the word and I will send it.