refactor(go): shrink internal/api to consumed models-only, adopt generated types in internal/rest

docs/api/oapi-codegen.yaml

@@ -4,8 +4,18 @@
 # spec stays consumable by the pinned generator; the Go module (Phase 1,
 # internal/api) reuses the same config so CI and codegen cannot drift.
 # The generator version is pinned in scripts/check-api-codegen.sh.
+#
+# Models only: internal/rest hand-writes the chi handlers and marshals these
+# generated types, so response shapes are compile-checked against the frozen
+# spec while goldens + the route-coverage test remain the value-level oracle.
+# If the spec unfreezes post-cutover and strict-server becomes worth its
+# routing rewrite, re-enable chi-server/strict-server here.
 package: api
 generate:
   models: true
-  chi-server: true
-  strict-server: true
+output-options:
+  # Go-binding overlay (date-time -> string; see that file's header). Path is
+  # relative to the go:generate working directory (internal/api).
+  overlay:
+    path: ../../docs/api/openapi-go-overlay.yaml
+    strict: true

docs/api/openapi-go-overlay.yaml

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: LicenseRef-FSL-1.1-Apache-2.0
+#
+# OpenAPI Overlay applied by oapi-codegen (docs/api/oapi-codegen.yaml) before
+# generating internal/api. Go-binding concerns only — this file must never
+# change the wire contract, which lives exclusively in openapi.yaml.
+#
+# Why: Go's time.Time marshals as RFC3339Nano (variable fractional digits),
+# but Node emits Date.toISOString() — always exactly ".000Z" millis. The
+# goldens fold timestamps to placeholders by key, so a format drift would be
+# invisible to the parity oracle. Binding date-time properties to plain Go
+# strings forces handlers to format explicitly (rest.isoMillis), keeping the
+# wire bytes identical to Node.
+overlay: 1.0.0
+info:
+  title: Go type bindings for the frozen ShellWatch wire contract
+  version: 1.0.0
+actions:
+  - target: $..[?(@.format == "date-time")]
+    description: Bind all date-time properties to plain strings (see header).
+    update:
+      x-go-type: string

docs/api/openapi.yaml

@@ -160,12 +160,15 @@ components:
       properties:
         status: { type: string, enum: [created] }
         id: { type: string }
+      required: [status, id]
     StatusUpdated:
       type: object
       properties: { status: { type: string, enum: [updated] } }
+      required: [status]
     StatusDeleted:
       type: object
       properties: { status: { type: string, enum: [deleted] } }
+      required: [status]
 
     TerminalStatus:
       type: string
@@ -193,7 +196,9 @@ components:
         mcpReason: { type: string }
         mcpClientName: { type: string }
         mcpClientVersion: { type: string }
-      required: [sessionId, endpointId, accountId, status, createdAt, source]
+      # lastActivityAt is always emitted: types.ts TerminalSession declares it
+      # non-optional and the manager sets it at create time.
+      required: [sessionId, endpointId, accountId, status, createdAt, lastActivityAt, source]
 
     Endpoint:
       type: object
@@ -227,6 +232,9 @@ components:
         current:
           type: boolean
           description: True for the first-party web-UI client.
+      # All keys are always emitted (auth-sessions.ts AuthSessionView declares
+      # every field non-optional; the two dates are explicit nulls when absent).
+      required: [clientId, clientName, scopes, authorizedAt, createdAt, current]
 
     PendingActionView:
       type: object