docs(githooks): replace pre-push hook with pre-commit and update documentation

.githooks/pre-push

@@ -1,18 +0,0 @@
-#!/bin/sh
-# Pre-push: the docs pages under apps/docs/content are generated from work/1
-# by `bun run sync`, and deploy.yml publishes whatever main holds. Regenerate
-# them now and refuse the push if the result differs from the tree, so a
-# solution never lands without its page (or with a stale `## Solution`).
-#
-# Bypass for a deliberate partial push: git push --no-verify
-set -eu
-
-cd "$(git rev-parse --show-toplevel)"
-report=$(bun run --silent sync)
-
-changed=$(git status --porcelain -- apps/docs/content)
-if [ -n "$changed" ]; then
-  printf '%s\n' "$report" | grep -v 'skipped (in sync)' >&2
-  printf '\npre-push: apps/docs/content is out of sync with work/1 — commit the regenerated pages:\n%s\n' "$changed" >&2
-  exit 1
-fi