Tree view: center a person between multiple spouses

family-chart 0.9.0 stacks all of a person's spouses on one gender-determined
side, so someone with two spouses (e.g. a woman with two husbands) renders
with both spouses piled above/below her and ambiguous child lines.

Patch the library (via patch-package) so the person stays centered and their
spouses split to alternating sides — spouse 1 above, spouse 2 below, further
spouses farther out — and order each couple's children to match, so children
descend from between the correct pair without crossed lines:

- setupSpouses: keep the person centered; place spouses at alternating
  offsets and recenter the cluster on the person's slot.
- sortChildrenWithSpouses: order children by spouse order (gender-independent)
  to match the new spouse positions.

Adds patch-package + a postinstall hook, and COPY patches into the Dockerfile
deps stage so the patch applies during `npm ci` in CI. Verified the patch
re-applies on a clean install and the production build passes.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Justin Paul <justin@jpaul.me>

frontend/Dockerfile

@@ -3,6 +3,9 @@
 FROM node:22-bookworm-slim AS deps
 WORKDIR /app
 COPY package.json package-lock.json ./
+# patches/ must be present before `npm ci` so the postinstall (patch-package)
+# can apply our vendored family-chart layout fix.
+COPY patches ./patches
 RUN npm ci
 
 FROM node:22-bookworm-slim AS build