fix: examples, model defaults and topic NUL bytes from SDK review

[ChiragAgg5k]

Fixes review findings on the SDK major PRs at their source.

Finding	Fix
PHP document examples use JSON objects (php -l fails)	Array examples that hold objects render as PHP arrays; list items get no keys; quotes in strings are escaped. 21 of 800 examples failed php -l before, 0 after
Ruby examples use null; GraphQL example has unescaped quotes	Empty optional numbers render nil; strings are single-quoted and escaped. 5 null literals and 1 parse error before, 0 after (ruby -c on all 800)
Dart getZone example typed models. result; DomainRegistrationType.new doesn't exist	Text responses are typed String; enum examples use the escaped member name (xnew). Same fix in the Flutter template
Python BackupRestoration.options defaults to [] (pydantic rejects it)	A map field's {} default renders as {}
Flutter Preferences.fromMap(null) throws when prefs is missing	Required nested models fall back to an empty map
Ruby Topic.path accepts NUL bytes	Every language's Topic helper rejects U+0000

e2e: new preset/settings and preset/profile mock endpoints return {}. Python and Dart/Flutter print preset settings: options=0 and preset profile: prefs=0, and every Topic program gains a nul case.

Watched red then green: Python313 (dict_type error), DartStable (type 'Null' is not a subtype of type 'Map<String, dynamic>') and Ruby31 (Topic nul:failed). Node20, PHP85 and Go118 also pass. GenerationTest passes, and the TS applyDefaults count goes from 5 to 6 for the new endpoint.

Closes #2052

[hansi-codes]

🔵 Tier A · Mergeable after minor fixes

The change appears sound, with one minor gap in automated coverage for generated Ruby example syntax.

This change updates generated Dart, Python, and Ruby examples and model handling, adds NUL validation to Topic helpers, and adds mock endpoints and e2e cases for map and nested-model defaults. It also updates generated Dart/Flutter docs and the generation/e2e fixtures for these cases.

Verdict	New comments	Fixed	Still open
✅ Approved	1	0	0

	Finding	Where
🟡	Add a syntax check for generated Ruby examples	src/SDK/Language/Ruby.php:298

Fix with agent prompt

### Issue 1
src/SDK/Language/Ruby.php:298
**Add a syntax check for generated Ruby examples**

This changes how Ruby example strings are escaped, but the generation suite has no Ruby equivalent of `testPhpExamplesParse()` to parse the emitted docs. A later quoting regression could reintroduce invalid examples without failing CI; adding a Ruby parse check for generated examples would keep this fix covered.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

📂 Walkthrough · 8

File	Change
src/SDK/Language/{Dart,Python,Ruby}.php	Adjusts enum example identifiers, Python map defaults, and Ruby example literals.
templates/dart/docs/example.md.twig; templates/flutter/docs/example.md.twig	Uses String for text responses in generated Dart examples.
templates/dart/lib/src/models/model.dart.twig	Defaults missing required nested model maps to an empty map.
templates/{android,dart,dotnet,go,kotlin,php,python,ruby,rust,swift,web}/**/*topic*	Rejects NUL characters in Topic path levels across generated SDKs.
mock-server/app/http.php; tests/resources/spec-openapi3.json	Adds preset settings and profile mock endpoints and schemas.
tests/e2e/Base.php; tests/e2e/*Test.php; tests/e2e/languages/**	Adds default-model and Topic NUL e2e cases.
templates/rust/tests/tests.rs	Adds a Rust unit-test case for Topic NUL validation.
tests/generation/GenerationTest.php	Updates the generated TypeScript defaults expectation.

---

_{Reviewed bec92d3 · Details · Comment @hansi-codes review to re-run, or mention @hansi-codes with a question.}

[hansi-codes]

🔵 Tier A · See the inline comments. Summary

[ChiragAgg5k]

@hansi-codes review

[hansi-codes]

🔵 Tier A · Looks good to merge. Summary

[hansi-codes]

Add a syntax check for generated Ruby examples

This changes how Ruby example strings are escaped, but the generation suite has no Ruby equivalent of testPhpExamplesParse() to parse the emitted docs. A later quoting regression could reintroduce invalid examples without failing CI; adding a Ruby parse check for generated examples would keep this fix covered.

Prompt To Fix With AI

This is a comment left during a code review.
Path: src/SDK/Language/Ruby.php
Line: 298

Comment:
**Add a syntax check for generated Ruby examples**

This changes how Ruby example strings are escaped, but the generation suite has no Ruby equivalent of `testPhpExamplesParse()` to parse the emitted docs. A later quoting regression could reintroduce invalid examples without failing CI; adding a Ruby parse check for generated examples would keep this fix covered.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{🟡 Minor · testing · Reply if this doesn't apply.}