docs: fix stale Docker paths and park region counts

Update /app/data → /app/backend/data across all docs to match the
volume mount fix from 3c91d9a. Add missing TZ env var to the web
container snippet in OPERATIONS.md. Correct Midwest (6→7) and
West & International (6→5) park counts in ARCHITECTURE.md.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/ARCHITECTURE.md

@@ -283,7 +283,7 @@ CREATE TABLE IF NOT EXISTS park_days (
 
 ### Storage
 
-- **Location**: `backend/data/parks.db` (or `/app/data/parks.db` in Docker)
+- **Location**: `backend/data/parks.db` (or `/app/backend/data/parks.db` in Docker)
 - **WAL journal files**: `parks.db-wal` and `parks.db-shm` accompany the main database
 - **Size**: Approximately 8,000-9,000 rows for a full year of 24 parks
 - **Not committed to git**: Listed in `.gitignore`
@@ -466,9 +466,9 @@ interface Park {
 **Regions:**
 - Northeast (6 parks): Great Adventure, New England, Great Escape, Darien Lake, Dorney Park, Canada's Wonderland
 - Southeast (3 parks): Over Georgia, Carowinds, Kings Dominion
-- Midwest (6 parks): Great America (IL), St. Louis, Cedar Point, Kings Island, Valleyfair, Worlds of Fun, Michigan's Adventure
+- Midwest (7 parks): Great America (IL), St. Louis, Cedar Point, Kings Island, Valleyfair, Worlds of Fun, Michigan's Adventure
 - Texas & South (3 parks): Over Texas, Fiesta Texas, Frontier City
-- West & International (6 parks): Magic Mountain, Discovery Kingdom, Knott's Berry Farm, California's Great America, Mexico
+- West & International (5 parks): Magic Mountain, Discovery Kingdom, Knott's Berry Farm, California's Great America, Mexico
 
 **Lookup utilities:**
 - `PARK_MAP`: `Map<string, Park>` for O(1) lookup by `id`