Disambiguate fetch-request-streams feature

Rewrite the fetch-request-streams feature to make it more clear what
precise property it covers, and add a new fetch-body-stream feature to
cover the `body` option to the `fetch` function supporting
`ReadableStream` objects.

Author: jgraham

features/fetch-body-stream.yml

@@ -0,0 +1,5 @@
+name: fetch ReadableStream body
+description: The `body` option passed to `fetch()` can be a `ReadableStream`.
+spec: https://fetch.spec.whatwg.org/#bodyinit
+compat_features:
+  - api.Request.Request.request_body_readablestream

features/fetch-body-stream.yml.dist

@@ -0,0 +1,11 @@
+# Generated from: fetch-body-stream.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support:
+    chrome: "105"
+    chrome_android: "105"
+    edge: "105"
+compat_features:
+  - api.Request.Request.request_body_readablestream

features/fetch-request-streams.yml

@@ -1,5 +1,5 @@
-name: Fetch upload streams
-description: A `fetch()` request uploads a stream of data to the server when a request's `body` property is a `ReadableStream` object.
+name: Request body property
+description: A `body` property representing a `ReadableStream` is available on `Request` objects returned by `fetch()`.
 spec: https://fetch.spec.whatwg.org/#concept-body-stream
 compat_features:
   - api.Request.body

features/fetch.yml

@@ -25,7 +25,6 @@ compat_features:
   - api.Request.Request.cross_origin_stripped
   - api.Request.Request.init_keepalive_parameter
   - api.Request.Request.init_referrer_parameter
-  - api.Request.Request.request_body_readablestream
   - api.Request.Request.response_body_readablestream
   - api.Request.arrayBuffer
   - api.Request.blob

features/fetch.yml.dist

@@ -442,13 +442,6 @@ compat_features:
   #   edge: "79"
   - api.Request.isHistoryNavigation
 
-  # baseline: false
-  # support:
-  #   chrome: "105"
-  #   chrome_android: "105"
-  #   edge: "105"
-  - api.Request.Request.request_body_readablestream
-
   # baseline: false
   # support:
   #   chrome: "131"