Feat/update client with 429 and job progress

[nhoening]

The client was not reacting properly to the 429 / Retry-After information.
We added some other improvements:

• report sparse information on job progress, rate-limits encountered
• opt asset update call sites into JSON parsing
• stop aggregation data after a site report fails

[coveralls]

Coverage Report for CI Build 35258960527

Coverage decreased (-0.8%) to 95.991%

Details

• Coverage decreased (-0.8%) from the base build.
• Patch coverage: 6 uncovered changes across 2 files (78 of 84 lines covered, 92.86%).
• 5 coverage regressions across 1 file.

Uncovered Changes

File	Changed	Covered	%
src/flexmeasures_client/response_handling.py	36	31	86.11%
src/flexmeasures_client/client.py	48	47	97.92%

Coverage Regressions

5 previously-covered lines in 1 file lost coverage.

File	Lines Losing Coverage	Coverage
src/flexmeasures_client/client.py	5	95.97%

---

Coverage Stats

Relevant Lines:	923
Covered Lines:	886
Line Coverage:	95.99%
Coverage Strength:	9.6 hits per line

---

💛 - Coveralls

[BelhsanHmida]

I reviewed and tested this PR locally and added two small fixes in separate commits:

• 38dcc9e preserves the positional constructor API released in v0.9.6 by making the new notification settings keyword-only. It also adds a regression test confirming that positional job_polling_* values still bind to the intended fields.
• 5d4f892 corrects the rate-limit recovery notice for passed-through error responses. A 429 followed by a 422 job response now reports the actual HTTP status instead of saying that the request succeeded, with a regression test covering that sequence.

Verification completed locally:

• Full test suite: 277 passed
• Full HEMS end-to-end run against an isolated current FlexMeasures server: passed
  • Asset setup, 14 initial ingestion jobs, six forecasts, all 12 scheduling simulation steps, per-step site/community aggregation, and final KPI reports completed successfully
  • The persisted workflow marker contains all five completed phases
  • A second resume run detected the completed setup and correctly skipped every phase

The core 429 retry behavior, Retry-After handling, job polling, and HEMS workflow changes otherwise look sound.