feat(progress): report machine-readable progress from every batch-machine step

[MiniCodeMonkey]

Batch machine now prints machine-readable progress lines while it downloads, unzips, reads and maps a source. ChopChop reads them from the container's stdout to show a progress bar, an ETA and a live map of which areas were processed and where rows failed. Turning progress off (OPENADDR_PROGRESS_INTERVAL=0) leaves output exactly as before.

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Changes

• openaddr/progress.py (new): a Reporter that prints {"progress":{...}} lines to stdout with print(..., flush=True), outside the logging module. One line when a phase starts, throttled lines while it runs (OPENADDR_PROGRESS_INTERVAL, default 15 s, 0 disables), and one when it ends. Each line carries phase, done, total (or null), unit, counters, and H3 resolution 6 cell deltas as [ok, fallback, error].
• openaddr/cache.py:
  • ArcGIS download: total is the get_feature_count() value the code already fetched and only logged.
  • URL download: counts bytes, with total from Content-Length when the server sends it.
• openaddr/conform.py:
  • Unzip: counts the uncompressed bytes.
  • Reading the source: OGR feature count; for GeoJSON, bytes of the file size; for CSV, rows with no total.
  • Mapping columns: rows, with the extract step's row count as the total.
  • Extract functions now return the number of rows they wrote.
• setup.py: adds h3 >= 4, < 5. The Dockerfile already installs through pip3 install ..
• Tests:
  • New openaddr/tests/progress.py covers the line shape, the null total, throttling, cell deltas, the disabled interval and non-finite coordinates.
  • A new ArcGIS test checks the first and final lines.
  • openaddr/tests/__init__.py defaults the interval to 0, so existing tests print nothing new.

Decisions

• Rate and ETA are not computed here. ChopChop computes them over a rolling window, so every tool only reports counts.
• phase_index/phase_count are left out, because the sequence of phases is not known up front.
• Map cells use representative_point() for non-point geometry, so polygon features land inside their shape.

Review notes

• Start with openaddr/progress.py, then the ArcGIS call site in cache.py, which is where most real sources spend their time.
• In the ArcGIS phase, done counts written features and counters.skipped counts skipped ones, so done can end below total.

Follow-ups

• The image build was only run on arm64. The amd64 h3 wheel should be confirmed in the first amd64 build.