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/ca/counties/sonoma/index.md

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

data/jurisdictions/us/states/ca/counties/sonoma/municipalities/healdsburg/people/oswaldo-jimenez.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Oswaldo Jimenez"
+description: "Mayor, Healdsburg, CA"
+role: "Mayor, Healdsburg, CA"
+level: "municipal"
+branch: "executive"
+state: "CA"
+tenure:
+  start: "2021-01-01"
+  current: true
+ids:
+  person: "51c57bf7-7b66-4c91-ad63-6f22d995ee02"
+  office: "17d4434a-28fb-49ca-8838-10251b4c57fd"
+  tenure: "5ad8cb1e-3ab3-4189-8f99-0266192129d6"
+  jurisdiction: "2e9d22ec-0cc1-4af5-bd51-6cff580adae1"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ca]
+timestamp: "2026-07-04"
+---
+
+# Oswaldo Jimenez
+
+Current Mayor, Healdsburg, CA.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/ca/counties/sonoma/municipalities/santa-rosa/people/chris-rogers.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Chris Rogers"
+description: "Mayor, Santa Rosa, CA"
+role: "Mayor, Santa Rosa, CA"
+level: "municipal"
+branch: "executive"
+state: "CA"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "a7561a9c-d130-42e8-8297-ab658d191e22"
+  office: "5b8dcca7-e3b5-4c78-854a-238975135150"
+  tenure: "9694e08b-67ab-423e-bc9e-471b5874d58a"
+  jurisdiction: "db6876e7-52ee-45eb-9da1-bb7df8e74ba3"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, ca]
+timestamp: "2026-07-04"
+---
+
+# Chris Rogers
+
+Current Mayor, Santa Rosa, CA.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).