Fix generated client wire names for renamed parameters

[Volv-G]

Problem

Two generator defects surfaced by a Binks review of a downstream codegen-only regeneration (Shopify/discovery#33919, follow-up r3880721261). Both are generator-owned: the downstream generated/ tree is only ever produced by regeneration, so hand-edits there would be reverted.

1. Renamed parameters were serialized with the Python local name.

_request_body_parameters reserves body in used_names, so a schema field actually named body becomes the Python identifier body_2. api_transport.py handles this correctly - it keys the wire payload off CliParameter.original_name while matching arguments against local_name. The static generator did not: _param_signature/_dict_literal used local_name for both the parameter and the JSON key. A normal call like admin_post_notices("text", title=..., variant=...) therefore sent {"body_2": ...} and omitted the server's required body. admin_patch_notices had the same defect for body updates.

The same mistake applied to the emitted params= and path_params= literals; it just was not observable in the current schema because body_2 is the only renamed parameter today.

2. The runtime template's type: ignore did not cover the required mypy error codes.

generate_runtime() emitted ConfigDict = None # type: ignore[assignment], which leaves downstream regenerations reporting runtime.py: Cannot assign to a type [misc] against an otherwise clean base.

Fix

• Thread original_name through _param_signature as a _ParamName(local_name, wire_name) pair, so the generated json_data, params, and path_params literals all use the OpenAPI wire name while the method signature keeps the collision-free Python local. Only a genuinely missing name falls back to the local identifier, so schema-valid empty property names keep their exact wire spelling.
• Emit # type: ignore[misc, assignment] in the runtime template and regenerate the checked-in tangle_api/generated/runtime.py.

Non-renamed parameters emit byte-identical literals, so the only change to the checked-in generated output is the one-line type: ignore.

Generated output for a colliding schema now reads:

def admin_notices(self, body_2: Any, order_by: Any = None, ...):
    return self._request_json(
        'POST', '/api/admin/notices',
        path_params=None,
        params={'order.by': order_by, 'token': token_2},
        json_data={**(body or {}), **{**{'body': body_2}, ...}},
        ...
    )

Tests

Three focused generator regressions in tests/test_codegen.py:

• test_generate_operations_uses_wire_names_for_renamed_parameters - renamed body (body -> body_2), query (order.by, token -> token_2) and path (notice-id) names; asserts both the emitted literals and the actual runtime call payloads through an imported generated module.
• test_generate_runtime_type_ignore_covers_required_mypy_error_codes - pins the runtime template's error codes and that generate() writes it verbatim.
• test_generate_operations_preserves_empty_wire_names - an empty JSON property name is schema-valid and must not be replaced by the generated local.

Checks

• uv run pytest - 1093 passed
• git diff --check clean, uv lock --check clean
• mypy on the regenerated runtime.py (with pydantic installed): clean, including under --warn-unused-ignores. Reverting to [assignment] alone reproduces Cannot assign to a type [misc].
• Independent local review completed; the empty-wire-name edge case above was found and fixed in review.

Downstream consumers need a submodule pin bump plus a regeneration to pick this up.