geo: measure the block street profile and fix the local CRS and origin

New Geo/scripts/street_profile.py measures the 279.4 m block centreline, the
three signalised crossings (20.9-25.9 m across), sidewalk centrelines at 12.6 m
and 13.6 m, and per-building setbacks of 13.0-15.8 m. Derived sidewalk widths
of ~4.0 m south and ~5.3 m north cross-check against the mapped centrelines.

Geo/manifests/local-origin.md fixes EPSG:26911 and the Highland intersection
node as origin, defines the axes and the x100 metre-to-centimetre rule, and
leaves the projected pair blank because PROJ is not installed here.

Records the lane-count discrepancy (4 tagged lanes over a 20.9 m carriageway).

ROADMAP.md

@@ -28,7 +28,7 @@ Status detail in [Docs/setup.md](Docs/setup.md); workstation audit in [Docs/envi
 
 - [x] Save a versioned OSM extract; document date, bounds, and source in `Geo/`.
 - [ ] Acquire separately licensed elevation data if needed.
-- [ ] In QGIS, set a suitable local projected CRS (e.g. EPSG:26911) and record a local origin.
+- [-] In QGIS, set a suitable local projected CRS (e.g. EPSG:26911) and record a local origin. CRS and origin point are fixed in `Geo/manifests/local-origin.md`; the EPSG:26911 easting/northing still has to be computed with PROJ/QGIS, which also confirms the transformation.
 - [x] Verify the address, building footprints, and demo boundaries for 6840 Hollywood Blvd against source data.
 - [ ] Import OSM blockouts through Blosm; clean and detail them in Blender.
 - [ ] Preserve geographic coordinates in metadata; define explicit meter→centimeter conversion to local Unreal coordinates.
@@ -48,7 +48,7 @@ Status detail in [Docs/setup.md](Docs/setup.md); workstation audit in [Docs/envi
 
 - [ ] First-person movement, mouse look, and Enhanced Input bindings.
 - [ ] Collision, reset, and pause functionality.
-- [ ] Walkable sidewalks and a designated street crossing.
+- [ ] Walkable sidewalks and a designated street crossing. Crossing chosen: mid-block signalised crossing, OSM way 385648319, at 130 m along the block (`Geo/verification/2026-11-06-street-profile.md`).
 - [ ] Fixed daytime lighting and basic ambience.
 - [ ] Geographic attribution display ("© OpenStreetMap contributors" + license link).