[260514-eanlcc] add path exclusion for infra dirs

[DarkCodePE]

Implements 260514-eanlcc

Layers

CLI + Core + FS + Test

Acceptance Criteria

AC-3: Path exclusion (.claude/helpers, .claude/hooks, .claude/rules skipped with log).

verify:
  - cmd: SMELL_SCAN_ENABLE=1 node .claude/helpers/smell-scanner.mjs --action scan --file .claude/helpers/foo.mjs --dry-run
    expect_stdout_match: excluded path, skipping
    expect_exit_code: 0

Dependencies

Slice 1 (module scaffold).

Definition of Done

AC-3 passes. Excluded path list hard-coded with override hook via .swarm/smell-config.json (read-only this slice; tunable only via env in later slice). Adds .swarm/smell-config.json.example template.

Plan

docs/plans/260514-eanlcc-smell-scanner.md (Slice 2)

[DarkCodePE]

[ac-verifier] closed: AC-1 pass, AC-2 pass, AC-3 pass, AC-4 pass, AC-5 pass, AC-6 pass, AC-7 pass, AC-8 pass, AC-9 pass. U-ID: 260514-eanlcc