wcc: drop @test fns from non-T builds, both stages (harec check.c:3941)

Splice @test N_FNDECLs out of the unit after the body-check passes,
mirroring harec's checked-but-not-emitted: a broken @test body still
errors loudly in non-T; @test-free units are emission-unchanged.
910/997 table rows pin keep/test x non-T/-T, head+consecutive unlink,
undef-body reject, and plain-calls-dropped loud link-fail. w6c+wwdump
combined.ww regen. (#6-team)

cmd/wcc/check.c

@@ -3228,4 +3228,38 @@ check_file(Checker *c, Node *file)
 		}
 	}
 	c->cur_mod = NULL;
+
+	/*
+	 * #6 harec-fidelity (ref/harec/src/check.c:3941): a @test fn is
+	 * fully checked above — pass 2 walked its body like every fn — but
+	 * is NOT emitted in a non-test build. harec skips append_decl for
+	 * FN_TEST && !is_test, so the fn never reaches unit->declarations
+	 * (the list codegen walks); the body is still type-checked, only the
+	 * emission is dropped. ww shares one file->list across check + cgen
+	 * (no separate checked-decl list, project_hare_ast_no_result), so we
+	 * splice the already-checked @test fns out here, after pass 2 — they
+	 * stay checked, never reach cg_file. The -T path is untouched: its
+	 * synth main calls the @test fns, so they must remain. Prereq for
+	 * in-package @test colocation (#9). Twin: selfhost/cmd/wcc/check.ww.
+	 */
+	if (!c->is_test) {
+		Node *prev = NULL;
+		for (Node *d = file->list; d; ) {
+			int istest = 0;
+			if (d->kind == N_FNDECL)
+				for (Node *at = d->attr; at; at = at->next)
+					if (at->str
+					    && strcmp(at->str, "test") == 0) {
+						istest = 1;
+						break;
+					}
+			Node *nx = d->next;
+			if (istest) {
+				if (prev == NULL) file->list = nx;
+				else prev->next = nx;
+			} else
+				prev = d;
+			d = nx;
+		}
+	}
 }