software-writer: sweeping-dead-code reports helpers defined in test files as test-only #58

plugins/software-writer/skills/sweeping-dead-code enumerates definitions in test files the same way as in production files. The Go search is --include='*.go' (references/tools/go.md), so it covers *_test.go. The Python search is --include='*.py', so it covers test_*.py. No step excludes test files or gives their definitions a class of their own.

The class table in SKILL.md:138 then assigns:

| `test-only` | Not reachable, not uncertain, and at least one test reference. |

Every helper, fixture factory or builder that is defined in a test file and called from tests meets this definition. Step 8 lists those rows under "test-only rows" (SKILL.md:157). They sit next to production code that only tests reach, which is the case the class exists for. Each such row also costs a refutation in Step 6.

The skill also has no per-stack definition of a test file. All five references/stacks/*/indirect-references.md say "references from test files do not count as callers" (line 3), and nothing says which files those are.

Relation to #48: the fix for #48 enumerates .bats files. It defines a bats test file as *.bats, setup_suite.bash, or a helper under the test directory, and it counts every reference inside a test file as a test reference. With that fix, every .bats helper that tests call is reported test-only. The fix applies the rule to bats only. This issue covers the other stacks and the class table.

Proposed fix:

• Define the test files per framework in each *-referenced-by-name.md.
• Classify a definition inside a test file by its own rule. For example: live when a test references it, dead when nothing references it. The test-only class would then keep its meaning: production code that only tests reach.
• Change the class table, Step 6 and the Step 8 report to match.