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/AGENTS.md

@@ -6,12 +6,12 @@
 **Pipeline A — Action Gating (*.json)**: Actions enter a pending queue and are
 classified by Claude via `vault-agent.sh`, which can auto-approve (call
 `vault-fire.sh` directly), auto-reject (call `vault-reject.sh`), or escalate
-to a human by writing `PHASE:escalate` to a phase file and sending a Matrix
-message — using the same unified escalation path as dev/action agents.
+to a human by writing `PHASE:escalate` to a phase file — using the same
+unified escalation path as dev/action agents.
 
 **Pipeline B — Procurement (*.md)**: The planner files resource requests as
 markdown files in `vault/pending/`. `vault-poll.sh` notifies the human via
-Matrix. The human fulfills the request (creates accounts, provisions infra,
+vault/forge. The human fulfills the request (creates accounts, provisions infra,
 adds secrets to `.env`) and moves the file to `vault/approved/`.
 `vault-fire.sh` then extracts the proposed entry and appends it to
 `RESOURCES.md`.
@@ -20,7 +20,7 @@ adds secrets to `.env`) and moves the file to `vault/approved/`.
 `run-rent-a-human` formula (via an `action` issue) when a task requires a human
 touch — posting on Reddit, commenting on HN, signing up for a service, etc.
 Claude drafts copy-paste-ready content to `vault/outreach/{platform}/drafts/`
-and notifies the human via Matrix for one-click execution. No vault approval
+and notifies the human via vault/forge for one-click execution. No vault approval
 needed — the human reviews and publishes directly.
 
 **Trigger**: `vault-poll.sh` runs every 30 min via cron.
@@ -31,15 +31,14 @@ needed — the human reviews and publishes directly.
 - `vault/PROMPT.md` — System prompt for the vault agent's Claude invocation
 - `vault/vault-fire.sh` — Executes an approved action (JSON) or writes RESOURCES.md entry (procurement MD)
 - `vault/vault-reject.sh` — Marks a JSON action as rejected
-- `formulas/run-rent-a-human.toml` — Formula for human-action drafts: Claude researches target platform norms, drafts copy-paste content, writes to `vault/outreach/{platform}/drafts/`, notifies human via Matrix
+- `formulas/run-rent-a-human.toml` — Formula for human-action drafts: Claude researches target platform norms, drafts copy-paste content, writes to `vault/outreach/{platform}/drafts/`, notifies human via vault/forge
 
 **Procurement flow**:
 1. Planner drops `vault/pending/<name>.md` with what/why/proposed RESOURCES.md entry
-2. `vault-poll.sh` notifies human via Matrix
+2. `vault-poll.sh` notifies human via vault/forge
 3. Human fulfills: creates account, adds secrets to `.env`, moves file to `vault/approved/`
 4. `vault-fire.sh` extracts proposed entry, appends to RESOURCES.md, moves to `vault/fired/`
 5. Next planner run reads RESOURCES.md → new capability available → unblocks prerequisite tree
 
 **Environment variables consumed**:
 - All from `lib/env.sh`
-- `MATRIX_TOKEN`, `MATRIX_ROOM_ID`, `MATRIX_HOMESERVER` — Escalation channel