Move blockchain app READMEs to centralized documentation

- Relocate blockchain-event-bridge README content to docs/apps/blockchain/blockchain-event-bridge.md
- Relocate blockchain-explorer README content to docs/apps/blockchain/blockchain-explorer.md
- Replace app READMEs with redirect notices pointing to new documentation location
- Consolidate documentation in central docs/ directory for better organization

apps/coordinator-api/README.md

@@ -1,55 +1,9 @@
 # Coordinator API
 
-## Purpose & Scope
+**Documentation has moved to:** [docs/apps/coordinator/coordinator-api.md](../../docs/apps/coordinator/coordinator-api.md)
 
-FastAPI service that accepts client compute jobs, matches miners, and tracks job lifecycle for the AITBC network.
+---
 
-## Marketplace Extensions
+This file has been migrated to the central documentation location. Please update your bookmarks and references to point to the new location.
 
-Stage 2 introduces public marketplace endpoints exposed under `/v1/marketplace`:
-
-- `GET /v1/marketplace/offers` – list available provider offers (filterable by status).
-- `GET /v1/marketplace/stats` – aggregated supply/demand metrics surfaced in the marketplace web dashboard.
-- `POST /v1/marketplace/bids` – accept bid submissions for matching (mock-friendly; returns `202 Accepted`).
-
-These endpoints serve the `apps/marketplace-web/` dashboard via `VITE_MARKETPLACE_DATA_MODE=live`.
-
-## Explorer Endpoints
-
-The coordinator now exposes read-only explorer data under `/v1/explorer` for `apps/explorer-web/` live mode:
-
-- `GET /v1/explorer/blocks` – block summaries derived from recent job activity.
-- `GET /v1/explorer/transactions` – transaction-like records for coordinator jobs.
-- `GET /v1/explorer/addresses` – aggregated address activity and balances.
-- `GET /v1/explorer/receipts` – latest job receipts (filterable by `job_id`).
-
-Set `VITE_DATA_MODE=live` and `VITE_COORDINATOR_API` in the explorer web app to consume these APIs.
-
-## Development Setup
-
-1. Create a virtual environment in `apps/coordinator-api/.venv`.
-2. Install dependencies listed in `pyproject.toml` once added.
-3. Run the FastAPI app via `uvicorn app.main:app --reload`.
-
-## Configuration
-
-Expects environment variables defined in `.env` (see `docs/bootstrap/coordinator_api.md`).
-
-### Signed receipts (optional)
-
-- Generate an Ed25519 key:
-  ```bash
-  python - <<'PY'
-  from nacl.signing import SigningKey
-  sk = SigningKey.generate()
-  print(sk.encode().hex())
-  PY
-  ```
-- Set `RECEIPT_SIGNING_KEY_HEX` in the `.env` file to the printed hex string to enable signed receipts returned by `/v1/miners/{job_id}/result` and retrievable via `/v1/jobs/{job_id}/receipt`.
-- Receipt history is available at `/v1/jobs/{job_id}/receipts` (requires client API key) and returns all stored signed payloads.
-- To enable coordinator attestations, set `RECEIPT_ATTESTATION_KEY_HEX` to a separate Ed25519 private key; responses include an `attestations` array alongside the miner signature.
-- Clients can verify `signature` objects using the `aitbc_crypto` package (see `protocols/receipts/spec.md`).
-
-## Systemd
-
-Service name: `aitbc-coordinator-api` (to be defined under `configs/systemd/`).
+For the complete documentation, see the [Coordinator API documentation](../../docs/apps/coordinator/coordinator-api.md).