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/ky/counties/oldham/index.md

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

data/jurisdictions/us/states/ky/counties/oldham/municipalities/goshen/people/bob-thacker.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Bob Thacker"
+description: "Mayor, Goshen, KY"
+role: "Mayor, Goshen, KY"
+level: "municipal"
+branch: "executive"
+state: "KY"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "a87d36ae-57b4-4874-8396-af0067e8aec2"
+  office: "1ffe4405-be9a-42f5-be98-17f4087b8a8b"
+  tenure: "4d964be2-a035-4210-b749-b595c4f63369"
+  jurisdiction: "78625171-8a6e-4bb2-be7a-19ffb957dab6"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ky]
+timestamp: "2026-07-04"
+---
+
+# Bob Thacker
+
+Current Mayor, Goshen, KY.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/ky/counties/oldham/municipalities/la-grange/people/john-black.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "John Black"
+description: "Mayor, La Grange, KY"
+role: "Mayor, La Grange, KY"
+level: "municipal"
+branch: "executive"
+state: "KY"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "effc200f-d796-4da5-b19f-c93e9903b57e"
+  office: "24cadebf-57bc-454b-9dc9-0b5d6c1717ae"
+  tenure: "48488c29-1510-4def-aebe-1f19c3193d6b"
+  jurisdiction: "c6c211c7-afb0-4321-b582-00c5b4680369"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ky]
+timestamp: "2026-07-04"
+---
+
+# John Black
+
+Current Mayor, La Grange, KY.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).