[chrischeng-c4]

Closes #36

Summary of Changes

• Intermediate Representation (crates/openapi-codegen/src/domain/ir/operations.rs):
  • Defined pub enum RetryClassIR { SafeRead, IdempotencyKey, NonRetryable, Unclassified } with Default pointing to Unclassified.
  • Added pub retry_class: RetryClassIR field to OperationIR.
  • In build_one, extracted x-retry-class vendor extension from op.extensions and mapped:
    • "safe-read" -> RetryClassIR::SafeRead
    • "idempotency-key" -> RetryClassIR::IdempotencyKey
    • "non-retryable" -> RetryClassIR::NonRetryable
    • Missing, unknown strings, or non-string values -> RetryClassIR::Unclassified.
  • Never inferred retry classification from HTTP method, is_query, or idempotency headers.
• Public API Re-export (crates/openapi-codegen/src/api/ir.rs):
  • Re-exported RetryClassIR alongside OperationIR in api::ir::operations.
• Unit Tests (crates/openapi-codegen/src/domain/ir/operations.rs):
  • Added 4 test cases covering:
    • retry_class_maps_known_extension_values: maps "safe-read", "idempotency-key", "non-retryable".
    • retry_class_defaults_to_unclassified_when_missing: missing extension defaults to Unclassified across get, post, delete, and query.
    • retry_class_defaults_to_unclassified_for_unknown_or_non_string_values: unknown strings ("yes") and non-string values (true, 42) default to Unclassified.
    • retry_class_reads_extension_on_additional_operations: vendor extension honored on additionalOperations.
• Negative Control:
  • Verified negative control: mutating build_one to set SafeRead for get when missing extension failed retry_class_defaults_to_unclassified_when_missing at the get assertion, and only rows expecting Unclassified failed.

Validation Evidence

• Affected Isolated Unit Tests (PASSED):
  cargo test --locked -p openapi-codegen --lib domain::ir::operations::tests:
  7 passed; 0 failed; 0 ignored; 102 filtered out
• Static Formatting (PASSED):
  cargo fmt -p openapi-codegen --check: clean exit 0.
• Static Compilation (PASSED):
  cargo check --locked -p openapi-codegen: clean exit 0.
• Unfiltered Package Test Record (CANCELED / PARTIAL FAILURE):
  An unfiltered package test run (cargo test --locked -p openapi-codegen) executed network/h2c/TLS suites, exhibiting partial failure on h2c connection tests and hanging on tls_alpn, and was terminated via task management (status: CANCELED). Per policy, local testing is strictly limited to isolated affected unit tests; package/integration tests belong in cloud CI.
• Local Tests NOT RUN:
  Local integration/h2c/server/network tests and full package suites are NOT RUN locally per confirmed test policy.
• Cloud MR Validation Needed:
  • Cloud MR affected unit, functional/e2e, and integration tests: PENDING (awaiting cloud CI execution upon PR submission).
  • Full release qualification matrix: NOT RUN (managed by release pipeline).