Move docs/ package mirror into document-navigator plugin

Relocate the ~6k-file docs tree from the repo root into
plugins/document-navigator/docs/ so the plugin is self-contained and
portable. docs/superpowers/ (specs and plans) stays at the repo root.

Moved via cp+rm rather than git mv because directory rename() fails with
EPERM on this WSL /mnt DrvFs mount; git rename-detection pairs the
identical-content files at commit time.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plugins/document-navigator/docs/communication/messaging/sms-providers/src/plivo/plivo.md

@@ -0,0 +1,66 @@
+# Plivo — `@suaveplan/sms-providers`
+
+<!-- begin:auto-docs -->
+_(no submodules)_
+<!-- end:auto-docs -->
+
+## Purpose
+
+Real Plivo SMS provider implementing `SmsProvider` from `@suaveplan/sms`. POSTs to `/v1/Account/{AuthId}/Message/` authenticated via HTTP Basic (`AuthId:AuthToken`); JSON body. Status fetched via `GET .../Message/{uuid}/`. Inbound webhook signature verification follows Plivo's documented `X-Plivo-Signature-V3` scheme — HMAC-SHA256 over the canonical signing string `<url><nonce><sorted form-fields joined as key=value, comma-separated>` with the auth token as the key, Base-64 encoded.
+
+The class holds no in-flight state and routes every HTTP call through the injectable `FetchLike` seam. Tests stand up a `node:http` server on a random port and inject a `fetch` adapter that points at it.
+
+## Features
+
+- HTTP Basic auth with the canonical `AuthId:AuthToken` pair.
+- JSON request body — `src`, `dst`, `text` (and `media_urls`/`type=mms` when MMS).
+- `getStatus(uuid)` round-trips the documented `.../Message/{uuid}/` resource.
+- Status mapping covers `queued` / `sent` / `delivered` / `undelivered` / `failed` / `rejected`.
+- `verifyWebhookSignature(url, nonce, params, sig)` implements the X-Plivo-Signature-V3 canonical string scheme.
+- `parseInbound` discriminates between inbound messages, delivery receipts, and opt-out/opt-in/help keywords.
+- OTel — counter + histogram on every send + verify.
+
+## Usage: Basic
+
+```ts
+import { PlivoProvider } from "@suaveplan/sms-providers";
+
+const plivo = new PlivoProvider({
+    authId: "MA…",
+    authToken: "…",
+});
+const r = await plivo.send({
+    to: "+15551234567",
+    from: "+15559999999",
+    body: "hi",
+});
+```
+
+## Usage: Advanced
+
+```ts
+import { PlivoProvider } from "@suaveplan/sms-providers";
+
+const plivo = new PlivoProvider({ authId: "MA…", authToken: "…" });
+const ok = await plivo.verifyWebhookSignature(
+    "https://your.app/webhooks/plivo",
+    "nonce-from-X-Plivo-Signature-Ma-Nonce-Header",
+    { From: "+1", To: "+2", Text: "hi", MessageUUID: "uuid" },
+    "<base64 signature>"
+);
+```
+
+## API Reference
+
+| Symbol | Kind | Notes |
+|---|---|---|
+| `PlivoProvider` | class | Implements `SmsProvider`. |
+| `send(message, options?)` | method | POST `.../Message/`; returns `SmsDeliveryReport`. |
+| `getStatus(uuid)` | method | `GET .../Message/{uuid}/`. |
+| `mapStatus(raw)` | method | Canonical mapping. |
+| `verifyWebhookSignature(url, nonce, params, sig)` | method | HMAC-SHA256-Base-64 verifier; throws `SIGNATURE_INVALID` on mismatch. |
+| `parseInbound(params)` | method | Discriminates into `InboundSmsEvent`. |
+
+## Implementation Notes
+
+`send` defaults the initial status to `"queued"` because Plivo's create response only returns the message UUID; the actual carrier-side state is later reported on the inbound DLR webhook. MMS support flips `type: "mms"` and forwards `mediaUrls` as `media_urls[]` per the documented Plivo convention.