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/ia/counties/johnson/index.md

@@ -32,7 +32,7 @@ timestamp: "2026-07-03"
 
 # Johnson County, IA
 
-County jurisdiction.
+County jurisdiction — 3 officeholders mapped.
 
 ## Demographics (ACS 2023)
 

data/jurisdictions/us/states/ia/counties/johnson/municipalities/coralville/people/meghann-foster.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Meghann Foster"
+description: "Mayor, Coralville, IA"
+role: "Mayor, Coralville, IA"
+level: "municipal"
+branch: "executive"
+state: "IA"
+tenure:
+  start: "2022-01-01"
+  current: true
+ids:
+  person: "323cea77-578d-491f-a239-b184758a1b28"
+  office: "ae650adb-e3ef-4021-a326-0c555ec1e3d7"
+  tenure: "c36da733-38fa-4258-a5b6-e49f044a39f7"
+  jurisdiction: "843122cc-928d-458f-af05-719fdf6fe8ce"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ia]
+timestamp: "2026-07-04"
+---
+
+# Meghann Foster
+
+Current Mayor, Coralville, IA.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/ia/counties/johnson/municipalities/iowa-city/people/bruce-teague.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Bruce Teague"
+description: "Mayor, Iowa City, IA"
+role: "Mayor, Iowa City, IA"
+level: "municipal"
+branch: "executive"
+state: "IA"
+tenure:
+  start: "2020-01-01"
+  current: true
+ids:
+  person: "f4ed4a72-225b-4cf5-863a-6be72d8b263c"
+  office: "cf36b86b-bdf5-47a4-bf6b-704e2772adc8"
+  tenure: "5786dd14-267b-4a45-bad1-bda563fc4e2e"
+  jurisdiction: "08e3a978-7a0a-4450-9c67-8a9ffb236ee3"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ia]
+timestamp: "2026-07-04"
+---
+
+# Bruce Teague
+
+Current Mayor, Iowa City, IA.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/ia/counties/johnson/municipalities/north-liberty/people/chris-hoffman.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Chris Hoffman"
+description: "Mayor, North Liberty, IA"
+role: "Mayor, North Liberty, IA"
+level: "municipal"
+branch: "executive"
+state: "IA"
+tenure:
+  start: "2022-01-01"
+  current: true
+ids:
+  person: "7f311d8e-a626-466d-ae56-8400e8e87fa9"
+  office: "620323e8-39f7-43f4-bb2b-a24e96abc2a7"
+  tenure: "a5d5db42-44bb-4faf-bca3-8337acb579e5"
+  jurisdiction: "fb91ffe4-4ef1-4f88-9228-e8850c2984d9"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ia]
+timestamp: "2026-07-04"
+---
+
+# Chris Hoffman
+
+Current Mayor, North Liberty, IA.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).