DSL quick-start docstring in dsl/__init__.py does not parse (uses non-existent 'latent'/'output' keywords)

[aaronstevenwhite]

Summary

The quivers.dsl package docstring (the "Quick start" in src/quivers/dsl/__init__.py) shows a program that does not parse under the released grammar. It uses latent f : X -> Y and output f, but neither latent, output, nor alias are keywords in the shipped tree-sitter grammar.

Repro (quivers 0.13.0)

from quivers.dsl import loads
loads("""
object X : FinSet 3
object Y : FinSet 4
latent f : X -> Y
output f
""")

quivers.dsl.parser.ParseError: syntax error at line 4, col 0: 'latent f : X -> Y'

Cause

• src/quivers/dsl/__init__.py lines ~15-22 (loads('''... latent f : X -> Y ... output f ''')).
• grep -oE '"(latent|output|alias)"' src/quivers/dsl/_grammar_data/grammar.json returns nothing on main (HEAD 4fefe49) — these tokens are not in the grammar.

The real surface is program NAME : A -> B with sample / let / observe / return steps and a top-level export NAME.

Expected

The docstring example should parse. Suggest replacing it with a minimal program that compiles, e.g.:

object Resp : FinSet 8
program m : Resp -> Resp
    sample b <- Normal(0.0, 5.0)
    observe y : Resp <- Normal(b, 1.0)
    return y
export m

Impact

First thing a user copies from the module docstring throws ParseError. Reproduces on main.