refactor: rename Processor to Webhook and Webhook to Entrypoint

The top-level entity that groups entrypoints and targets is now called
Webhook (was Processor). The inbound URL endpoint entity is now called
Entrypoint (was Webhook). This rename affects database models, handler
comments, routes, and README documentation.

closes #12

README.md

@@ -2,7 +2,7 @@
 
 webhooker is a Go web application by [@sneak](https://sneak.berlin) that
 receives, stores, and proxies webhooks to configured targets with retry
-support, observability, and a management web UI. License: pending.
+support, observability, and a management web UI. License: MIT.
 
 ## Getting Started
 
@@ -88,15 +88,14 @@ monolithic database:
 - **Main application database** — Stores application configuration and
   all standard webapp data: users, sessions, API keys, and global
   settings.
-- **Per-processor databases** — Each processor (working name — a better
-  term is needed) gets its own dedicated SQLite database file containing:
-  input logs, processor logs, and all output queues for that specific
-  processor.
+- **Per-webhook databases** — Each webhook gets its own dedicated SQLite
+  database file containing: input logs, webhook logs, and all output
+  queues for that specific webhook.
 
-This separation provides several benefits: processor databases can be
-independently backed up, rotated, or archived; a high-volume processor
+This separation provides several benefits: webhook databases can be
+independently backed up, rotated, or archived; a high-volume webhook
 won't cause lock contention or bloat affecting the main application; and
-individual processor data can be cleanly deleted when a processor is
+individual webhook data can be cleanly deleted when a webhook is
 removed.
 
 ### Package Layout
@@ -120,9 +119,9 @@ The main entry point is `cmd/webhooker/main.go`.
 ### Data Model
 
 - **Users** — Service users with username/password (Argon2id hashing)
-- **Processors** — Webhook processing units, many-to-one with users
-- **Webhooks** — Inbound URL endpoints feeding into processors
-- **Targets** — Delivery destinations per processor (HTTP, retry, database, log)
+- **Webhooks** — Webhook processing units, many-to-one with users
+- **Entrypoints** — Inbound URL endpoints feeding into webhooks
+- **Targets** — Delivery destinations per webhook (HTTP, retry, database, log)
 - **Events** — Captured webhook payloads
 - **Deliveries** — Pairing of events with targets
 - **Delivery Results** — Outcome of each delivery attempt
@@ -170,7 +169,7 @@ The main entry point is `cmd/webhooker/main.go`.
 - [ ] Analytics dashboard (success rates, response times)
 
 ### Phase 5: API
-- [ ] RESTful CRUD for processors, webhooks, targets
+- [ ] RESTful CRUD for webhooks, entrypoints, targets
 - [ ] Event viewing and filtering endpoints
 - [ ] API documentation (OpenAPI)
 
@@ -182,7 +181,7 @@ The main entry point is `cmd/webhooker/main.go`.
 
 ## License
 
-Pending — to be determined by the author (MIT, GPL, or WTFPL).
+MIT License. See [LICENSE](LICENSE) for details.
 
 ## Author