Municipals: nest 1,823 city officeholders under their real counties

Pull Atlas's place→county crosswalk (Census TIGER 2024 places × county
geometries, 32,041 places) into the build as a committed raw input, and
use it to resolve municipal officeholders whose county was unknown.

- data/place_county_crosswalk.jsonl — new raw input (place_geoid → county_geoid)
- build.py — place-name+state → county_geoid → ACS county slug as a fallback
  in county_slug(); city_slug() generalized to non-FL bare place labels
- data/sources/sources.yaml — provenance entry for the crosswalk

_unresolved municipals: 1919 → 58. The remainder are genuine: CT planning
regions (post-county), county-level rows mislabeled municipal upstream,
consolidated city-counties (null label), Wikidata-QID placeholder names,
and ambiguous same-name places — left unresolved rather than guessed.

Join key is county_geoid (5-digit FIPS); the directory slug is taken from
the ACS county node so municipals nest under the exact existing county dir.
Deterministic (byte-identical rebuild); validate.py passes 19,721 records.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

data/jurisdictions/us/states/tx/counties/jefferson/index.md

@@ -32,7 +32,7 @@ timestamp: "2026-07-03"
 
 # Jefferson County, TX
 
-County jurisdiction.
+County jurisdiction — 2 officeholders mapped.
 
 ## Demographics (ACS 2023)
 

data/jurisdictions/us/states/tx/counties/jefferson/municipalities/beaumont/people/roy-west.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Roy West"
+description: "Mayor, Beaumont, TX"
+role: "Mayor, Beaumont, TX"
+level: "municipal"
+branch: "executive"
+state: "TX"
+tenure:
+  start: "2023-05-01"
+  current: true
+ids:
+  person: "e396754b-90c0-49ec-b79a-9f591b0112ac"
+  office: "f90aeb0d-cf9b-4531-bda6-97278bdf510b"
+  tenure: "d0d3bb67-e925-4195-8bfb-914d5a01517b"
+  jurisdiction: "2a4cdfb8-ebfe-48b9-9f4b-7f9fdc7f3bee"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, tx]
+timestamp: "2026-07-04"
+---
+
+# Roy West
+
+Current Mayor, Beaumont, TX.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/tx/counties/jefferson/municipalities/port-arthur/people/thurman-bill-bartie.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Thurman \"Bill\" Bartie"
+description: "Mayor, Port Arthur, TX"
+role: "Mayor, Port Arthur, TX"
+level: "municipal"
+branch: "executive"
+state: "TX"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "51465dcb-478d-4cb0-a7fe-35d83632e2df"
+  office: "08dcc4b2-1374-4f02-8b9c-8c9833655523"
+  tenure: "ca28627b-509f-4110-bc25-d6e962e58cf8"
+  jurisdiction: "59fd64af-61da-4f41-ae06-71d2ce786289"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, tx]
+timestamp: "2026-07-04"
+---
+
+# Thurman "Bill" Bartie
+
+Current Mayor, Port Arthur, TX.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).