[BUG] [typescript-angular] queryParamObjectFormat=key doesn't work correctly after v7.11.0 on typescript-angular generator

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Starting from v7.12.0, the angular-typescript generator makes invalid web requests :

v7.11.0:
It was working correctly.
?limit=25&offset=0&filter%5Bterms%5D=&filter%5Bmember%5D=1&filter%5BconnectionType%5D=wireless
-> ?limit=25&offset=0&filter[terms]=&filter[member]=1&filter[connectionType]=wireless

v7.12.0:
The parameter queryParamObjectFormat was completely ignored and the json format was used.
?limit=25&offset=0&filter=%7B%22terms%22%3A%22%22%2C%22member%22%3A1%2C%22connectionType%22%3A%22wired%22%7D
-> ?limit=25&offset=0&filter={"terms":"","member":1,"connectionType":"wired"}

v7.13.0:
Everything is flat, and thus, wrong.
?limit=25&offset=0&terms=&member=1&connectionType=wired

This is a regression, it was correctly working on previous versions.
Something has changed between the v7.12.0 and v7.13.0 but there is still something wrong.

Generation Details

docker run --rm -u $(CURRENT_UID):$(CURRENT_GID) -v ${PWD}:/local openapitools/openapi-generator-cli:v7.13.0 generate -i /local/openapi/spec.yaml -g typescript-angular -o "/local/frontend_angular/src/app/api" --additional-properties=queryParamObjectFormat=key

Start with the typescript-angular generation command in the report and compare generated client requests between v7.11.0, v7.12.0, and v7.13.0 using queryParamObjectFormat=key. Trace the generated query-parameter serialization, then verify that nested object keys produce the expected bracketed query format rather than JSON or flattened parameters.