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.

bench/diagnose.py

@@ -23,14 +23,14 @@ import json
 from pathlib import Path
 import sys
 
-from freeroute.board import build_board
-from freeroute.board.search_tree import ShapeSearchTree
-from freeroute.dsn import parse_dsn
-from freeroute.geometry.octagon import overlaps_2d
-from freeroute.route import grid_router
-from freeroute.route.exact_router import route_board_exact
-from freeroute.route.grid_router import GridRouter, _ends_of
-from freeroute.route.pipeline import (
+from rpmroute.board import build_board
+from rpmroute.board.search_tree import ShapeSearchTree
+from rpmroute.dsn import parse_dsn
+from rpmroute.geometry.octagon import overlaps_2d
+from rpmroute.route import grid_router
+from rpmroute.route.exact_router import route_board_exact
+from rpmroute.route.grid_router import GridRouter, _ends_of
+from rpmroute.route.pipeline import (
     _mm_to_board,
     _net_widths_board,
     _rule_clearance_dsn,