chore: update changelog, remove stale files, scrub VPS IP

- CHANGELOG.md: add [Unreleased] 2026-04-16 section covering settings
  page, admin tools, password reset, re-extract, community page, SSE
  upload progress, and all bug fixes since 2026-04-10
- Remove docs-proposal.md (internal planning doc, not user-facing)
- Remove publish/ directory (leftover artefacts from publish.sh, not
  meant to be tracked)
- scripts/pull_feedback.sh: replace hardcoded default VPS IP with a
  required positional argument to avoid leaking server address
- docs/squash-for-github.md: document the squash-for-github commit
  strategy for future reference

scripts/pull_feedback.sh

@@ -1,9 +1,9 @@
 #!/usr/bin/env bash
 # Pull user feedback from the VPS into ./feedback/ locally.
-# Usage: bash scripts/pull_feedback.sh [vps-host]   (default: root@95.216.55.151)
+# Usage: bash scripts/pull_feedback.sh <user@host>
 
 set -e
-VPS=${1:-root@95.216.55.151}
+VPS=${1:?Usage: $0 user@host}
 REMOTE=/var/bincio/data/_feedback
 LOCAL=$(dirname "$0")/../feedback