- fetchers/shared: config loader, atomic incoming writer, state
  persistence (cursor + seen-files), poll loop with exponential backoff
- fetchers/api_fetcher: JWT auth with auto-refresh, windowed paginated
  fetcher (continuous + backfill modes, param_variants for RSL/TSL),
  entry point, example config.yml, Dockerfile (build ctx ./fetchers)
- fetchers/api_fetcher/mock_server: minimal Flask mock with JWT auth
  and synthetic hourly CML data (POST /login/, POST /refresh/, GET /cml/)

Parses JSON files produced by api_fetcher.  A field map (loaded from
FIELD_MAP_PATH env var) does longest-prefix matching on the filename
stem to route source fields to [time, cml_id, sublink_id, rsl, tsl].
Includes example_field_map.yml for the mock server (RSL + TSL split).

parser/service_logic.py: import parse_api_json_raw; add elif .json
  branch routing JSON files to write_rawdata (before else: quarantine)
parser/main.py: add .json to FileWatcher extensions; add *.json glob
  in process_existing_files for startup replay
docker-compose.dev.yml: adds mock_server (port 5001) and api_fetcher
  services for local development; mounts shared data volume and
  example field_map.yml

fetcher.py: in continuous mode, end was computed as start+chunk_hours;
  with overlap_seconds >= chunk_hours*3600 (as in the example config) the
  window end equalled the cursor, so the cursor never advanced (infinite
  loop). Fix: end = cursor_dt + chunk_hours; overlap only shifts start back.

parser/main.py: process_existing_files returned early when there were no
  CSV files, skipping the JSON glob entirely. Fix: guard only the CSV
  section, always run the JSON section.

mock_server/app.py + docker-compose.dev.yml: healthcheck hit GET /login/
  which is POST-only; Flask returned 405, urlopen raised HTTPError, check
  always failed → api_fetcher never started. Fix: add GET /health endpoint,
  point healthcheck there.

service_logic.py: the JSON elif was placed AFTER 'raw'/'data' in name,
  but all api_fetcher filenames end in _data.json and matched the CSV
  branch first, making the JSON branch unreachable. Fix: check .json
  suffix first, before the substring checks.

test_service_logic.py: add test_process_cml_file_json_archived covering
  the repaired JSON branch (patches parse_api_json_raw, asserts write
  and archive calls).

test_api_json_parser.py: new test module for parse_api_json_raw covering
  prefix matching, RSL/TSL column routing, UTC datetime normalisation,
  empty-file handling, and error paths (missing field, no prefix match).

…nfrastructure with API fetcher

Resolution adds api_json support to the new ParserBundle architecture:

- Add load_api_json_bundle() helper in service_logic.py
- Wire api_json parser selection in main.py based on PARSER_TYPE env var
- Update generate_config.py validation to accept 'api_json' as valid parser type
- Import _make_default_bundle in main.py for test compatibility

This preserves all api_fetcher functionality (JSON polling, api_json parser)
while adopting the pluggable parser infrastructure from csv-generic-parser PR.