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>

vault/vault-fire.sh

@@ -83,7 +83,6 @@ if [ "$IS_PROCUREMENT" = true ]; then
 
   if [ -z "$ENTRY" ]; then
     log "ERROR: $ACTION_ID has no '## Proposed RESOURCES.md Entry' section"
-    matrix_send "vault" "❌ Procurement $ACTION_ID has no RESOURCES.md entry — cannot fire" 2>/dev/null || true
     exit 1
   fi
 
@@ -95,7 +94,6 @@ if [ "$IS_PROCUREMENT" = true ]; then
   mv "$ACTION_FILE" "${VAULT_DIR}/fired/${ACTION_ID}.md"
   rm -f "${LOCKS_DIR}/${ACTION_ID}.notified"
   log "$ACTION_ID: approved → fired (procurement)"
-  matrix_send "vault" "✅ Procurement fulfilled: ${ACTION_ID} — RESOURCES.md updated" 2>/dev/null || true
   exit 0
 fi
 
@@ -175,9 +173,7 @@ if [ "$FIRE_EXIT" -eq 0 ]; then
     && mv "$TMP" "${VAULT_DIR}/fired/${ACTION_ID}.json"
   rm -f "$ACTION_FILE"
   log "$ACTION_ID: approved → fired"
-  matrix_send "vault" "✅ Vault fired: ${ACTION_ID} (${ACTION_TYPE} from ${ACTION_SOURCE})" 2>/dev/null || true
 else
   log "ERROR: $ACTION_ID fire failed (exit $FIRE_EXIT) — stays in approved/ for retry"
-  matrix_send "vault" "❌ Vault fire failed: ${ACTION_ID} (${ACTION_TYPE}) — will retry" 2>/dev/null || true
   exit "$FIRE_EXIT"
 fi