Further root readme bump, factor `.clearing` content

In line with our move to `uv` and recent `nix` support update a bunch of
the summary content and factor out the order-control section to a new
`.piker.clearing` readme file with embedded todos therein.

README.rst

@@ -43,11 +43,12 @@ focus and feats:
 fitting with these tenets, we're always open to new
 framework/lib/service interop suggestions and ideas!
 
-- **100% federated**: your code, your hardware, your data feeds, your broker fills.
+- **100% federated**
+  your code, your hardware, your data feeds, your broker fills.
 
-- **zero web**: low latency as a prime objective, native UIs and
-                modern IPC protocols without trying to re-invent the
-                "OS-as-an-app"..
+- **zero web**
+  low latency as a prime objective, native UIs and modern IPC
+  protocols without trying to re-invent the "OS-as-an-app"..
 
 - **maximal privacy**: prevent brokers and mms from knowing your
                        planz; smack their spreads with dark volume