feat: migrate from npm to bun and fix analytics map height

Switch package manager and runtime from Node.js/npm to Bun across
Docker, CI, and scripts. The SQLite driver remains better-sqlite3
due to Next.js Turbopack being unable to resolve bun:sqlite during
build-time page pre-rendering.

Also fix the world map not rendering in the analytics page — the
overflowX wrapper added for mobile broke the flex height chain,
collapsing the map to 0px.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker/web/Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1.6
 
-FROM node:25-slim AS base
+FROM oven/bun:1-slim AS base
 WORKDIR /app
 
 FROM base AS deps
@@ -12,9 +12,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     openssl \
     ca-certificates \
     && rm -rf /var/lib/apt/lists/*
-COPY package.json package-lock.json* ./
-# Install dependencies
-RUN if [ -f package-lock.json ]; then npm ci; else npm install; fi
+COPY package.json bun.lock ./
+RUN bun install --frozen-lockfile
 
 FROM base AS builder
 ENV NODE_ENV=production
@@ -25,7 +24,7 @@ ENV DATABASE_URL=file:/tmp/build.db
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
 # Build the Next.js application
-RUN npm run build && rm -f /tmp/build.db
+RUN bun run build && rm -f /tmp/build.db
 
 FROM base AS runner
 # Accept build args for user/group IDs to support rootless operation