# 1.0.0-beta.18 JSON String Token Parsing Foundation

## Scope

Slovo-facing `1.0.0-beta.18` adds one narrow `std.json` facade name for JSON
string token parsing:

- `parse_string_value_result ((token string)) -> (result string i32)`

The helper is a thin source wrapper over the promoted compiler/runtime name
`std.json.parse_string_value_result`. The existing JSON construction helpers
from `1.0.0-beta.7` and primitive scalar parse helpers from `1.0.0-beta.17`
remain intact.

## Contract

`parse_string_value_result` consumes one already-isolated ASCII JSON string
token. The token must start and end with quotes and must not include leading or
trailing whitespace outside those quotes. Success returns `ok decoded_text`;
ordinary parse failure returns `err 1`.

The token parser decodes the simple JSON escapes `\"`, `\\`, `\/`, `\b`,
`\f`, `\n`, `\r`, and `\t`. It rejects raw control bytes, bad escapes,
unterminated strings, trailing bytes after the closing quote, raw non-ASCII,
and all `\uXXXX` escapes for this slice.

## Non-Scope

This is not full JSON parsing. It does not add object parsing, array parsing,
recursive `JsonValue`, tokenizer APIs, generic parse APIs,
whitespace-tolerant document parsing, streaming decoders or encoders, schema
validation, Unicode escape decoding or normalization, embedded NUL policy,
stable API freeze, stable ABI/layout, or performance claims.

## Gate-Supporting Compiler Hardening

The beta18 release also includes a bounded `glagol test` stack hardening fix:
test execution runs on a worker thread with a 16 MiB stack. This is not a new
language feature. It keeps deep source-authored stdlib fixtures gateable through
normal `glagol test` behavior instead of host process stack overflow, and is
covered by the promotion gate's stdlib fixture test execution.
