Remove deprecated hydro, zonal, focal and classify aliases for 1.0.0 #3762

Reason or Problem

Four deprecated spellings in hydro, zonal, focal and classify still work and warn with DeprecationWarning. 1.0.0 is where they go away: the stability policy (PR #3761) says removals happen only in a major release, and 1.0.0 is the first one.

Proposal

Remove the compatibility shims and the tests that exercise them:

• basins / basins_d8 (xrspatial.hydro, the top-level re-export, and the .xrs.basins accessor method). Use basin / basin_d8.
• crop(zones_ids=...) in xrspatial.zonal. Use zone_ids=.
• raster= on focal.apply and hotspots. Use agg=.
• The wrapper on natural_breaks that remaps a positional num_sample from the pre-1.0 (agg, num_sample, name, k) order. The signature is (agg, k, num_sample, name); pass num_sample= by keyword.

After this, the old spellings raise the ordinary TypeError or AttributeError. No custom error messages.

The removed spellings and their replacements are listed on the migration page added in #3761 (docs/source/user_guide/migration_1_0.rst).

Stakeholders and Impacts

Breaking change, 1.0.0 only. Code that ran on 0.10.20 without warnings is not affected. Part of the release gate in #2930.