merge: pull mhiqrambg/9router-mibp-version into master

Merge the MIBP fork (v1.0.14, synced to decolua v0.5.81) into our master
(0.5.86) at merge-base a8c9d380. Keep HEAD's infra policy (untracked
lockfile, mirror-configurable Dockerfile, decolua GHCR/DockerHub, README)
while absorbing the fork's engine features:

- feat(providers): freebuff provider + executor + OAuth + usage tracking
- feat(providers): cline free-tier models, Freebuff catalog sync
- feat(proxy-pools): pool egress geo probe, proxy-pool fitness + retry
- fix(usage): hide noAuth providers (devin-cli, mimo-free) from usage list
- test(harness): DATA_DIR isolation so tests never write the real DB
- fix(codebuddy-intl): probe token in connection test, OAuth by identity
- chore(guards): durable markers so fixes aren't silently dropped

Resolutions:
- registry/index.js regenerated deterministically (122 providers, alpha
  order). trae/windsurf/devin-cli stay hidden per HEAD security posture
  (no tool-calling / local-agent shell access) — not re-enabled.
- nonStreamingHandler: drop the generic unconditional unwrapDataEnvelope
  call; envelope unwrap stays scoped to clineEnvelope-quirk providers
  (unwrapClineEnvelope), fixing a latent mibp bug where non-opted-in
  providers ({success,data} bodies) were stripped.
- Drop fork-local Docker lockfile policy (package-lock.json, AGENTS.md,
  .npmrc verify scripts): this repo keeps package-lock untracked (nix
  build deploy). .npmrc (audit=false/fund=false) kept.
- Keep gitbook-pages workflow enabled (ours); mibp disabled it.
- Restore 13 upstream tests mibp deleted (they cover features we keep).

Verified: 2841 tests, 2687 pass, fail set byte-identical to HEAD (zero
new regressions); providers/alias/oauth baselines regenerated to merged
code and all green.

scripts/test-combo-autoswitch.mjs

@@ -2,9 +2,14 @@
 // Sends text / image / search requests to a combo and reports which member ran.
 //   node scripts/test-combo-autoswitch.mjs
 const BASE = process.env.BASE_URL || "http://localhost:20127";
-const KEY = process.env.API_KEY || "sk-6581be4f05a82b6b-uxy6jn-c8190ea8";
+const KEY = process.env.API_KEY;
 const COMBO = process.env.COMBO || "haha";
 
+if (!KEY) {
+  console.error("API_KEY environment variable is required");
+  process.exit(1);
+}
+
 // 16x16 PNG (valid image so vision providers accept it).
 const PNG = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAAFklEQVR4nGO4I2JDEmIY1TCqYfhqAAAeBCwQ8YdREQAAAABJRU5ErkJggg==";