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/ut/counties/iron/index.md

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

data/jurisdictions/us/states/ut/counties/iron/municipalities/cedar-city/people/garth-green.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Garth Green"
+description: "Mayor, Cedar City, UT"
+role: "Mayor, Cedar City, UT"
+level: "municipal"
+branch: "executive"
+state: "UT"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "e7cd29e0-732c-499d-b962-276a169f299a"
+  office: "6661244f-798e-4a52-b3c1-b034f4ed67fc"
+  tenure: "31ca94c7-3ee7-4e49-a67a-9b4968c1d656"
+  jurisdiction: "e5eb11fc-7846-450b-99fd-ef218879779f"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ut]
+timestamp: "2026-07-04"
+---
+
+# Garth Green
+
+Current Mayor, Cedar City, UT.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/ut/counties/iron/municipalities/parowan/people/mollie-halterman.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Mollie Halterman"
+description: "Mayor, Parowan, UT"
+role: "Mayor, Parowan, UT"
+level: "municipal"
+branch: "executive"
+state: "UT"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "6dc83e19-6b48-4621-a9e5-e9f5f9accbef"
+  office: "34556c37-709b-4309-a231-8d3c8ade8e93"
+  tenure: "8c8b5506-d274-48e3-a48b-7fa3638f2624"
+  jurisdiction: "83d71eef-f429-4ec2-98e5-0f4255c734ec"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ut]
+timestamp: "2026-07-04"
+---
+
+# Mollie Halterman
+
+Current Mayor, Parowan, UT.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).