Ban source comments — dsl/test + src/v2/test .dag (deletion-only)

[gunbai-bot]

Strips all source comments (// line + /* */ block) from dsl/test/** and src/v2/test/** .dag files. Part of the codebase-wide comment ban (sibling of pilot #5534): source comments are a parallel-ledger / dual-representation anti-pattern (DESIGN §2 no dual representation, §6 the mark on the carrier is the authority).

Deletion-only, no logic changes. Applied the shared string-literal-aware stripper scripts/strip_dag_comments.py (preserves // inside URL strings, multi-line strings, char literals). The few + lines are code lines that merely had a trailing comment removed — code is token-for-token identical (verified git diff).

Verification (by execution)

• Build: cargo build --release --bin gunbc green.
• Dual-root compile-clean (--source-root src/v2 --source-root dsl --target rust): exactly 2 diagnostics, both the pre-existing intentionally-broken negative fixtures (layering_scan/dsl_extdeps_v4_exact/extdeps/plant.dag, layering_scan/parse_level_pre_resolve/std/plant.dag) — the baseline, not a regression. No other errors.
• Witness discovery intact: 224 test fn declarations before == 224 after. (Raw "test fn" grep dropped 247→242 only because 5 were prose mentions inside deleted comments.)
• 0 stray free comments remain in scope; doc-reachability/dangling-link safe (markdown doc links live in string literals, preserved; no bind: provenance refs in test comments).

🤖 Generated with Claude Code