fix: Remove Matrix integration — notifications move to forge + OpenClaw (#732)

Remove all Matrix/Dendrite infrastructure:
- Delete lib/matrix_listener.sh (long-poll daemon), lib/matrix_listener.service
  (systemd unit), lib/hooks/on-stop-matrix.sh (response streaming hook)
- Remove matrix_send() and matrix_send_ctx() from lib/env.sh
- Remove MATRIX_HOMESERVER auto-detection, MATRIX_THREAD_MAP from lib/env.sh
- Remove [matrix] section parsing from lib/load-project.sh
- Remove Matrix hook installation from lib/agent-session.sh
- Remove notify/notify_ctx helpers and Matrix thread tracking from
  dev/dev-agent.sh and action/action-agent.sh
- Remove all matrix_send calls from dev-poll.sh, phase-handler.sh,
  action-poll.sh, vault-poll.sh, vault-fire.sh, vault-reject.sh,
  review-poll.sh, review-pr.sh, supervisor-poll.sh, formula-session.sh
- Remove Matrix listener startup from docker/agents/entrypoint.sh
- Remove append_dendrite_compose() and setup_matrix() from bin/disinto
- Remove --matrix flag from disinto init
- Clean Matrix references from .env.example, projects/*.toml.example,
  formulas/*.toml, AGENTS.md, BOOTSTRAP.md, README.md, RESOURCES.md,
  PHASE-PROTOCOL.md, and all agent AGENTS.md/PROMPT.md files

Status visibility now via Codeberg PR/issue activity. Human interaction
via vault items through forge. Proactive alerts via OpenClaw heartbeats.

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

.woodpecker/agent-smoke.sh

@@ -105,7 +105,6 @@ echo "=== 2/2  Function resolution ==="
 # Excluded — not sourced inline by agents:
 #   lib/tea-helpers.sh      — sourced conditionally by env.sh (tea_file_issue, etc.); checked standalone below
 #   lib/ci-debug.sh         — standalone CLI tool, run directly (not sourced)
-#   lib/matrix_listener.sh  — standalone systemd daemon (not sourced)
 #   lib/parse-deps.sh       — executed via `bash lib/parse-deps.sh` (not sourced)
 #   lib/hooks/*.sh          — Claude Code hook scripts, executed by the harness (not sourced)
 #
@@ -189,7 +188,6 @@ check_script lib/guard.sh
 # Standalone lib scripts (not sourced by agents; run directly or as services).
 # Still checked for function resolution against LIB_FUNS + own definitions.
 check_script lib/ci-debug.sh
-check_script lib/matrix_listener.sh
 check_script lib/parse-deps.sh
 
 # Agent scripts — list cross-sourced files where function scope flows across files.