Rename to rpmroute

The router began as a port of FreeRouting and has grown its own engine
(negotiated congestion, tree nets, exact checks, axis escapes), and
'freeroute' was one letter from the project it no longer follows. The
package, module and command are now rpmroute; the freeroute command stays
as an alias, and the RPMROUTE / RPMROUTE_ORACLE_JAVA variables fall back
to the old FREEROUTE names. Version 2026.10.07. Routing is unchanged: a
PCBench board routes to a byte-identical session either way.

tests/geometry/test_line.py

@@ -5,7 +5,7 @@ Oracles hand-derived from ``geometry/planar/Line.java``.
 
 from __future__ import annotations
 
-from freeroute.geometry import IntPoint, Line, RationalPoint, Side
+from rpmroute.geometry import IntPoint, Line, RationalPoint, Side
 
 
 def test_side_of_point():
@@ -79,7 +79,7 @@ def test_intersection_approx_matches_exact():
 def test_translate_and_opposite():
     line = Line.from_coords(0, 0, 4, 0)
     assert line.opposite().direction().equals(line.direction()) is False
-    from freeroute.geometry import IntVector
+    from rpmroute.geometry import IntVector
 
     moved = line.translate_by(IntVector(0, 5))
     assert moved.side_of(IntPoint(2, 5)) == Side.COLLINEAR