Add Lium as a price source

[surcyf123]

Adds Lium (https://lium.io), a GPU rental marketplace, as a price source.

Source. https://lium.io/api/public/v1/nodes is a public, unauthenticated JSON feed of every rentable node, with per-GPU and per-node hourly USD prices (docs). robots.txt allows /api/public/.

What scraper/sources/lium.py does

• Keeps on-demand nodes. Skips the spot tier, which is reclaimable, in line with the README's on-demand-only rule.
• Normalizes Lium's model strings (H100 80GB HBM3, A100-SXM4-80GB, B300 SXM6 PC, RTX A6000) before canonical_model.
• Uses "<model> x<count>" as the instance type, so collapse_regions publishes one row per model and GPU count at its cheapest country, and keeps the per-country prices in regions.
• Sets availability from available_gpu_count. deploy_url is the node's rent page.

Wiring. One JOBS entry with a minimum of 5 rows, a README sources-table row, and test_lium_skips_spot_and_normalizes_names.

Checks. pytest -q tests passes (9). A live dry run today returned 21 rows across 15 models, none quarantined by the price bounds.

dstackai/gpuhunt#259 adds Lium to the gpuhunt catalog. Once that ships, the gpuhunt source could take Lium instead, and I'm happy to switch to that if you prefer one route.

🤖 Generated with Claude Code

[surcyf123]

@kchandan, a gentle ping on this one. It adds Lium as an on-demand price source from our public nodes feed. If you'd like anything changed (the source format, tests, or skipping the spot tier differently), say so and I'll update it.