fix(test): a generic function called from a test block works

Test blocks were never type-checked, and the checker is what makes a
generic call real; they are checked like entry now. Reseed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

LANGUAGE.md

@@ -1782,7 +1782,8 @@ ludicc app.ludic --emit-llvm -o app.ll   # stop at LLVM IR
 ```
 
 A test program is a file of `test "name" { ... }` blocks with `expect(cond)`, `expect_eq(a, b)` and
-`expect_near(a, b, tol)` in them. `ludic test` finds `tests/*.ludic` and `src/**/*_test.ludic`;
+`expect_near(a, b, tol)` in them; a test block is type-checked like `entry`, so a generic function
+called from one works as it does anywhere. `ludic test` finds `tests/*.ludic` and `src/**/*_test.ludic`;
 given a directory, it runs every `*_test.ludic` under it and every file straight inside a `tests/`
 directory under it. **Each test block runs in a process of its own**, so a global one test changes
 is back to its initial value in the next - no test depends on another having run, or not. A