Publish sanitized P2Pool hashrate stats

Enable P2Pool's --data-api/--local-api and add a small stdlib-only sidecar
that copies an allowlist of numeric fields (node/sidechain hashrate,
connected miners, shares, network difficulty) to /p2pool/stats.json. Worker
IPs and wallet fragments in local/stratum are never served.

An Ingress adds that single path to the website host (www.eom.dev by
default), so the homepage can read it same-origin and reuse its TLS cert.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018STDcc5BaYxPMNA9S8Wycs

README.md

@@ -22,6 +22,33 @@ Optional:
   stop earning once they leave its PPLNS window.
 - `monero_p2pool_addpeers` (default `[]`): extra P2Pool peers as `host:port`.
   They must be on the same chain.
+- `monero_p2pool_stats_host` (default `www.eom.dev`): website host that gets
+  the public `/p2pool/stats.json` path. Use `""` to keep stats internal.
+- `monero_p2pool_stats_ingress_class` (default `nginx`), `monero_p2pool_stats_image`
+  (default `python:3.13-alpine`).
+
+Public stats
+------------
+
+P2Pool runs with `--data-api /api --local-api`. Those files include miner IP
+addresses, so they are never served. A `stats` sidecar
+(`files/p2pool_stats.py`, standard library only) copies an allowlist of numeric
+fields into one JSON document:
+
+    {"sidechain": "nano",
+     "node":    {"hashrate_15m", "hashrate_1h", "hashrate_24h", "miners",
+                 "shares_found", "shares_failed", "current_effort",
+                 "average_effort", "reward_share_percent",
+                 "last_share_found_time", "updated_at", "stale"},
+     "pool":    {"hashrate", "miners", "difficulty", "height", "blocks_found",
+                 "last_block_found_time", "pplns_window", "updated_at", "stale"},
+     "network": {"hashrate", "difficulty", "height", "reward_xmr",
+                 "updated_at", "stale"}}
+
+`node` is this P2Pool instance (everyone mining through it); `pool` is the
+whole sidechain. Sections are `null` until P2Pool writes them, and the
+endpoint answers 503 until `node` exists. Run the sidecar's tests with
+`python3 -m unittest discover -s tests`.
 
 Example Playbook
 ----------------