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/me/counties/cumberland/index.md

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

data/jurisdictions/us/states/me/counties/cumberland/municipalities/portland/people/mark-dion.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Mark Dion"
+description: "Mayor, Portland, ME"
+role: "Mayor, Portland, ME"
+level: "municipal"
+branch: "executive"
+state: "ME"
+tenure:
+  start: "2024-01-01"
+  current: true
+ids:
+  person: "bf82a8b1-4526-4214-8056-87e3e862322c"
+  office: "d79e89ef-6c00-46fa-8cfd-04ec18785f8f"
+  tenure: "348c172d-5e88-4c1d-8710-06eedee1df1f"
+  jurisdiction: "ae3a86b4-a7e6-42ad-b1a0-c9876df4b658"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, me]
+timestamp: "2026-07-04"
+---
+
+# Mark Dion
+
+Current Mayor, Portland, ME.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/me/counties/cumberland/municipalities/south-portland/people/misha-c-pride.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "Misha C. Pride"
+description: "Mayor, South Portland, ME"
+role: "Mayor, South Portland, ME"
+level: "municipal"
+branch: "executive"
+state: "ME"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "c6f83e1d-f2fc-4e93-b7d2-603bf2ae7c28"
+  office: "2f88c12d-3a6f-4a36-b696-f29915dabeee"
+  tenure: "6a8629c3-5f27-4cb3-a3fb-f9f07aff30a0"
+  jurisdiction: "270c6fa4-3fcd-4e25-857c-920b61dfc896"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, me]
+timestamp: "2026-07-04"
+---
+
+# Misha C. Pride
+
+Current Mayor, South Portland, ME.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).

data/jurisdictions/us/states/me/counties/cumberland/municipalities/westbrook/people/david-morse.md

@@ -0,0 +1,39 @@
+---
+type: Person
+title: "David Morse"
+description: "Mayor, Westbrook, ME"
+role: "Mayor, Westbrook, ME"
+level: "municipal"
+branch: "executive"
+state: "ME"
+tenure:
+  start: "2026-06-20"
+  current: true
+ids:
+  person: "c07ab3ee-ed9f-4cf1-bfe9-4ec931f8c4d2"
+  office: "3ebe7eae-5818-413a-933e-12a79890dcbb"
+  tenure: "a1bb8bfe-324b-4bdd-a59a-67eb57dc179e"
+  jurisdiction: "0a2a6d20-5078-460a-a0b3-3a9f41b57704"
+sources:
+  - field: office
+    source: "Wikidata"
+  - field: tenure
+    source: "Wikidata"
+  - field: jurisdiction
+    source: "Census TIGER 2024"
+confidence: official
+tags: [officeholder, municipal, executive, me]
+timestamp: "2026-07-04"
+---
+
+# David Morse
+
+Current Mayor, Westbrook, ME.
+
+## Sources
+
+- office: Wikidata
+- tenure: Wikidata
+- jurisdiction: Census TIGER 2024
+
+Generated from the Atlas officeholders v3 export (2026-07-04).