feat(matrix): land QA follow-ups and refresh docs

- harden Matrix onboarding/chat lifecycle after manual QA
- refresh README and Matrix docs to match current behavior
- add local ignores for runtime artifacts and include current planning/report docs

Closes #7
Closes #9
Closes #14

bot-examples/bwrap-claude

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# Sandboxed wrapper for Claude Code using bubblewrap.
+# Restricts filesystem access: DATA_DIR is writable, system is read-only.
+#
+# Usage: bwrap-claude <claude-command> [args...]
+#   bwrap-claude claude -p --verbose ...
+#   bwrap-claude claude-zai -p --verbose ...
+#
+# Requires: bubblewrap (apt install bubblewrap)
+
+set -euo pipefail
+
+DATA_DIR="${DATA_DIR:?DATA_DIR must be set}"
+
+exec bwrap \
+    --ro-bind / / \
+    --tmpfs /tmp \
+    --tmpfs /run \
+    --tmpfs /root \
+    --proc /proc \
+    --dev /dev \
+    --bind "$DATA_DIR" "$DATA_DIR" \
+    --bind "$HOME/.claude" "$HOME/.claude" \
+    --bind-try "$HOME/.claude-zai" "$HOME/.claude-zai" \
+    --setenv HOME "$HOME" \
+    --setenv DATA_DIR "$DATA_DIR" \
+    --die-with-parent \
+    --new-session \
+    "$@"