Merge remote-tracking branch 'origin/main' into feat/235-async-contract

# Conflicts:
#	docs/decisions.md

ErsatzTV/wwwroot/openapi/v1.json

@@ -565,7 +565,7 @@
           "Blocks"
         ],
         "summary": "Replace a block and its items",
-        "description": "Replaces the block's name/minutes/stop-scheduling and its full item list. Item indexes are assigned from the array order. Minutes must be greater than zero, divisible by 5, and at most 24 hours.",
+        "description": "Replaces the block's name/minutes/stop-scheduling and its full item list. Item indexes are assigned from the array order. Minutes must be greater than zero, divisible by 5, and at most 24 hours. Send the ETag from the items GET as If-Match to reject a stale overwrite with 412 (issue #253); a successful response carries the new ETag.",
         "parameters": [
           {
             "name": "id",
@@ -623,6 +623,26 @@
               }
             }
           },
+          "400": {
+            "description": "Bad Request",
+            "content": {
+              "text/plain": {
+                "schema": {
+                  "$ref": "#/components/schemas/ProblemDetails"
+                }
+              },
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ProblemDetails"
+                }
+              },
+              "text/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ProblemDetails"
+                }
+              }
+            }
+          },
           "404": {
             "description": "Not Found",
             "content": {
@@ -643,6 +663,26 @@
               }
             }
           },
+          "412": {
+            "description": "Precondition Failed",
+            "content": {
+              "text/plain": {
+                "schema": {
+                  "$ref": "#/components/schemas/ProblemDetails"
+                }
+              },
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ProblemDetails"
+                }
+              },
+              "text/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ProblemDetails"
+                }
+              }
+            }
+          },
           "422": {
             "description": "Unprocessable Entity",
             "content": {
@@ -672,6 +712,7 @@
           "Blocks"
         ],
         "summary": "Get block items",
+        "description": "Returns the block's items and a strong ETag of the block's version. Pass that ETag back as If-Match on the replace (PUT) to detect a concurrent edit (issue #253).",
         "parameters": [
           {
             "name": "id",