docs: retire the /graphql endpoint contract and its protocol-page residue (#10845)

* docs: retire the /graphql endpoint contract and protocol residue (#10832)

/graphql is not mounted. `packages/runtime/src/http-dispatcher.ts:2026` records
its removal, there is no `createGraphQLDomain` among the domains registered at
`http-dispatcher.ts:556-574`, and no `handleGraphQL` survives outside CHANGELOGs.

Remove-vs-rewrite follows the 404/501 distinction in
`packages/runtime/src/domains/unavailable.ts`: 404 = the route is not there;
501 = the route is there, the implementation is not. /graphql is in neither
state, so it belongs in neither row of a catalog of servable routes.

Deleted (the construct asserts a surface that does not exist):
- `api/plugin-endpoints.mdx` — the whole `### GraphQL (/graphql)` section and
  its POST method/path table, plus GraphQL from the frontmatter enumeration.
- `api/declarative-endpoints.mdx` — /graphql from the exemplar list pointing at
  that catalog; the two remaining examples are real mounted routes.
- `protocol/diagram.mdx` — the `GQL[GraphQL]` node AND both its edges
  (`CLIENT --> GQL`, `GQL --> KERNEL`); mermaid materialises an undeclared node
  from a dangling edge, so deleting the declaration alone still renders a box.
- `protocol/diagram.mdx` — GraphQL from the `src/api/` layer-table cell;
  that directory contains zero graphql files (re-measured).

Rewritten (the surrounding claim is true; only the enumeration was wrong):
- `protocol/diagram.mdx` sequence label → `HTTP Request (REST)`.
- `protocol/kernel/lifecycle.mdx` → `Start HTTP server`, box width preserved.
- `protocol/kernel/error-handling.mdx` → `(HTTP, WebSocket)`.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DdCnBGcHeufjrq7drTD3wt

* docs(api): reflow the plugin-endpoints callout after the /graphql removal

Keeps the em dash attached to the clause it belongs to instead of orphaning
it at the start of a line, and refills the paragraph. No claim changes.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DdCnBGcHeufjrq7drTD3wt

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: os-zhuang

content/docs/api/declarative-endpoints.mdx

@@ -12,9 +12,9 @@ publish gates serves real traffic as soon as the package is published.
 
 <Callout type="warn">
 **This is not [Plugin Endpoints](/docs/api/plugin-endpoints).** That page is a *catalog of
-built-in routes* the platform serves when a plugin is installed (`/auth`, `/automation`,
-`/graphql`, …) — you call those, you do not write them. This page is about the endpoints
-**you declare**, which live under your own namespace and never overlap with that catalog.
+built-in routes* the platform serves when a plugin is installed (`/auth`, `/automation`, …) —
+you call those, you do not write them. This page is about the endpoints **you declare**,
+which live under your own namespace and never overlap with that catalog.
 </Callout>
 
 ## Which channel: `actions` or `apis`?

content/docs/api/plugin-endpoints.mdx

@@ -1,6 +1,6 @@
 ---
 title: Plugin Endpoints
-description: REST endpoints that become available when the corresponding plugin is installed — auth, workflow, automation, views, realtime, notifications, AI, i18n, GraphQL, and file storage.
+description: REST endpoints that become available when the corresponding plugin is installed — auth, workflow, automation, views, realtime, notifications, AI, i18n, and file storage.
 ---
 
 # Plugin Endpoints
@@ -142,12 +142,6 @@ protocol `ai.chatStream` parses and owns message state for you.
 | GET | `/i18n/translations/:locale` | Get translation bundle |
 | GET | `/i18n/labels/:object/:locale` | Get field labels |
 
-### GraphQL (`/graphql`) — Plugin Required
-
-| Method | Endpoint | Description |
-|:-------|:---------|:------------|
-| POST | `/graphql` | Execute GraphQL query/mutation |
-
 ### File Storage (`/storage`) — Plugin Required
 
 Provided by `@objectstack/service-storage`, which registers these routes on the

content/docs/protocol/diagram.mdx

@@ -22,7 +22,7 @@ ObjectStack is composed of seven protocol layers that work together to form a co
 | **System (Kernel)** | `src/kernel/` | Manifest, Datasources, Plugins, Kernel |
 | **Automation** | `src/automation/` | Flows, Workflows, Triggers, Approvals |
 | **AI** | `src/ai/` | Agents, RAG Pipelines, Model Registry |
-| **API** | `src/api/` | REST, GraphQL, WebSocket, Realtime |
+| **API** | `src/api/` | REST, WebSocket, Realtime |
 | **Security** | `src/security/` | Permissions, Roles, Sharing, RLS |
 
 ---
@@ -39,7 +39,6 @@ graph TB
 
     subgraph "API Layer"
         REST[REST Endpoints]
-        GQL[GraphQL]
         WS[WebSocket / Realtime]
     end
 
@@ -92,12 +91,10 @@ graph TB
 
     %% Client to API
     CLIENT --> REST
-    CLIENT --> GQL
     CLIENT --> WS
 
     %% API references Data
     REST --> KERNEL
-    GQL --> KERNEL
     WS --> KERNEL
 
     %% Security enforced at Kernel
@@ -160,7 +157,7 @@ sequenceDiagram
     participant D as Driver
     participant DB as Database
 
-    C->>API: HTTP Request (REST / GraphQL)
+    C->>API: HTTP Request (REST)
     API->>K: Parsed Operation
 
     K->>SEC: Check Permissions

content/docs/protocol/kernel/error-handling.mdx

@@ -7,7 +7,7 @@ import { AlertCircle, Bug, Shield, Info, AlertTriangle, XCircle, Radio, Zap } fr
 
 # Error Handling
 
-The **Error Handling Protocol** defines standardized error codes, response formats, and debugging strategies across all ObjectStack APIs (HTTP, WebSocket, GraphQL).
+The **Error Handling Protocol** defines standardized error codes, response formats, and debugging strategies across all ObjectStack APIs (HTTP, WebSocket).
 
 ## Why Standardized Errors Matter
 

content/docs/protocol/kernel/lifecycle.mdx

@@ -67,7 +67,7 @@ The ObjectStack boot process follows a **strict order** to ensure dependencies a
 │  └─ Start event bus                                             │
 │  └─ Start job scheduler                                         │
 │  └─ Start audit logger                                          │
-│  └─ Start HTTP/GraphQL servers                                  │
+│  └─ Start HTTP server                                           │
 └─────────────────────────────────────────────────────────────────┘
                           ↓
 ┌─────────────────────────────────────────────────────────────────┐