Prevent Windows debug stack overflows

[attahn]

Splits the large recursive type-checking and code-generation dispatchers into bounded handlers, preventing stack overflows on Windows debug builds without changing behavior.

Adds a regression covering 32 nested builtin calls and a 20-call method chain. The previous debug compiler overflows on this fixture; the refactored compiler passes it. Comments preserve the reason for the deliberately split dispatch structure.

Verified with cargo test --bin mako (78 passed) and the focused Mako regression test.

Summary by CodeRabbit

• Bug Fixes

  • Improved reliability of debug builds on Windows by preventing stack overflows when processing deeply nested expressions and chained calls.
  • Preserved stable behavior for complex arithmetic, nested error handling, and method-call expressions.

• Build Improvements

  • Development builds now use settings that keep deep type checking and code generation within the default Windows stack limit.

• Tests

  • Added coverage for deeply nested expressions and chained method calls to help prevent regressions.

[attahn]

@coderabbitai[bot] review

[coderabbitai]

📝 Walkthrough

Walkthrough

The type checker is refactored into dedicated expression and builtin-call helpers. Development profile settings, a deep expression-stack example, Windows CI coverage, and an unreleased changelog entry are added.

Changes

Type-checking and stack validation

Layer / File(s)	Summary
Builtin call dispatch src/types/mod.rs	Builtin matching is centralized and builtin typing is distributed across five helper groups while call-site safety, deprecation, task, and generic checks remain in check_call_expr.
Expression typing helpers src/types/mod.rs	Typing for expression variants is extracted into dedicated helpers, including identifiers, operators, literals, conversions, control flow, indexing, fields, methods, and concurrency expressions.
Expression dispatcher wiring src/types/mod.rs	check_expr routes expression variants to the extracted helpers and retains inline string interpolation handling.
Windows debug stack validation Cargo.toml, examples/testing/deep_expr_stack_test.mko, .github/workflows/ci.yml, CHANGELOG.md	Development optimization is set to level zero, deep nested expressions and chained method calls are tested, Windows CI runs the test, and the build change is documented.

Estimated code review effort: 4 (Complex) | ~45 minutes

Suggested reviewers: loreste

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the main change: preventing Windows debug stack overflows in debug builds.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

@attahn: I’ll review the changes, with particular attention to preserving dispatch behavior and the regression coverage for deeply nested calls.

✅ Action performed

Review finished.

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