chore(brand): rename the product to ReplyPier

The upstream project name is gone from code, assets, docs and build
output: brand strings, domains (replypier.site and its app/api/docs/help
subdomains), env prefixes, image and network names, the widget's public
JS API (window.ReplyPier, replypierId/BaseUrl/Config/Token), CSS tokens
(--rp-*), file and directory names, and the WordPress plugin package.

- widget loader is now webclient/replypier.min.js; both bundles rebuilt
  from source (backend/assets/widget.{js,css}, frontend/public/webclient)
- NOTICE, llms.txt, CONTRIBUTING, HELP_CENTER_INFRA and config.dev.js
  rewritten rather than string-swapped; the demo config no longer ships
  the previous vendor's Firebase/Razorpay/Google keys
- new migration replypier_ai_model_001 adds REPLYPIER to the managed
  AIModelType and rewrites pre-rename rows
- local compose project, database, role and volume renamed; LOCAL_DEPLOY
  documents carrying the old local data over

backend/app/services/meta_own_app.py

@@ -1,5 +1,5 @@
 """
-Copyright 2024-2026 ChatterMate
+Copyright 2024-2026 ReplyPier
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 
 WhatsApp numbers and Messenger Pages that live in the customer's own Meta
-app (connected with manual credentials) rather than in ChatterMate's.
+app (connected with manual credentials) rather than in ReplyPier's.
 
 Meta signs their webhooks with the customer's app secret, which the shared
 /webhooks/meta endpoint can't check. So each such account gets its own
@@ -95,7 +95,7 @@ async def resolve_own_app(access_token: str, entered_secret: Optional[str],
     """The customer's own app behind this token, proven with its secret —
     the one entered, or else the one kept from the last connect (checked
     again: the new token may be from another app). None without a secret, or
-    for ChatterMate's own app, whose webhooks the shared address already gets.
+    for ReplyPier's own app, whose webhooks the shared address already gets.
 
     Raises AppSecretMismatch or AppCheckUnavailable."""
     secret = entered_secret or (own_app_secret(previous) if previous is not None else None)