fix(plugin): revert default to 3456 + correct v3.16.1 narrative; v3.16.2 (#96)

v3.16.1's narrative ("OCP server moved to 3478 default in v3.14+") was
incorrect. OCP source default has been 3456 since 593d0dc (initial
release) and never changed. The single observation of 3478 is the
maintainer's Mac mini, whose plist was rewritten with --port 3478
during a 2026-05-08 PR #71 dogfood smoke-test accident (see
~/.cc-rules/memory/learnings/subagent_setup_mjs_prod_host_collision.md).
The drift was never reconciled and v3.16.1 mistakenly canonised the
post-accident port as the new default.

This release reverts:
- ocp-plugin/index.js fallback → http://127.0.0.1:3456
- openclaw.plugin.json configSchema.proxyUrl.default → http://127.0.0.1:3456
- README §Environment Variables CLAUDE_PROXY_PORT default → 3456
- top-level package.json → 3.16.2

PR #95's env-reading path (OCP_PROXY_URL → CLAUDE_PROXY_PORT → fallback)
is preserved — that part was good design and stays. Only the hardcoded
fallback default changes.

Hosts whose OCP plist injects a non-default port must also inject the
same CLAUDE_PROXY_PORT into the OpenClaw plist for the plugin to follow
(documented in the new index.js comment block).

Mac mini's plist was reverted from 3478 to 3456 as part of this deploy
(per-host correction; no source code reflects host-specific state).

CHANGELOG includes an explicit erratum entry under v3.16.1 marking it
superseded.

Process note: this PR was triggered by maintainer asking "why was the
port changed?" — the answer revealed I (PM) wrote v3.16.1's CHANGELOG
without running `git log -G "3478" -- setup.mjs`. Iron Rule 2
(evidence-first) was violated. Future commits asserting historical
facts must include the grep that confirmed them.

No cli.js citation needed: OCP-internal plugin + docs, no server.mjs
change.

Co-authored-by: dtzp555 <dtzp555@gmail.com>
Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

ocp-plugin/index.js

@@ -3,15 +3,17 @@
  * Calls the local claude-proxy and formats the response.
  *
  * Port resolution (in priority order):
- *   1. OCP_PROXY_URL env (full URL, e.g. http://10.0.0.5:3478)
+ *   1. OCP_PROXY_URL env (full URL, e.g. http://10.0.0.5:3456)
  *   2. CLAUDE_PROXY_PORT env (port only; localhost assumed)
- *   3. Fallback: http://127.0.0.1:3478 (OCP v3.14+ default)
+ *   3. Fallback: http://127.0.0.1:3456 (OCP server source default since v1.0)
  *
- * (The legacy 3456 default — pre-v3.14 — caused "OCP error: fetch failed"
- * on machines whose OCP server moved to 3478 while the plugin lagged.)
+ * If a particular host's OCP plist injects a non-default CLAUDE_PROXY_PORT,
+ * the OpenClaw launchd plist for that host must also inject the same
+ * CLAUDE_PROXY_PORT into the plugin's env, or the plugin will fall back to
+ * 3456 and miss the server.
  */
 const PROXY = process.env.OCP_PROXY_URL
-  || (process.env.CLAUDE_PROXY_PORT ? `http://127.0.0.1:${process.env.CLAUDE_PROXY_PORT}` : "http://127.0.0.1:3478");
+  || (process.env.CLAUDE_PROXY_PORT ? `http://127.0.0.1:${process.env.CLAUDE_PROXY_PORT}` : "http://127.0.0.1:3456");
 
 // Wrap output in monospace code block for Telegram/Discord alignment
 function mono(text) { return "```\n" + text + "\n```"; }

ocp-plugin/openclaw.plugin.json

@@ -2,14 +2,14 @@
   "id": "ocp",
   "name": "OCP Commands",
   "description": "Slash commands for the OpenClaw Proxy — /ocp usage, /ocp settings, /ocp health, etc.",
-  "version": "3.16.1",
+  "version": "3.16.2",
   "configSchema": {
     "type": "object",
     "additionalProperties": false,
     "properties": {
       "proxyUrl": {
         "type": "string",
-        "default": "http://127.0.0.1:3478",
+        "default": "http://127.0.0.1:3456",
         "description": "URL of the Claude proxy. Overridable via OCP_PROXY_URL or CLAUDE_PROXY_PORT env."
       }
     }