docs: InitConfig creates the repo; tailoring it is a MergeConfigPr

Caught by argus reviewing the seven-site correction that just landed:
ApprovalKind::InitConfig still read "for manager customisation", the
same phrase family, two variants above the MergeConfigPr doc that
already described the PR flow correctly.

Ambiguous rather than flatly wrong, but it sits in the wire type both
surfaces read, so it gets the same treatment as the rest.

hive-sh4re/src/lib.rs

@@ -94,8 +94,11 @@ pub enum ApprovalKind {
     /// Create + start a new sub-agent container with the given name
     /// (under the default `agent.nix` template).
     Spawn,
-    /// Seed an agent's proposed config repo for manager customisation
-    /// (step 1 of the two-step spawn flow).
+    /// Create an agent's config repo and seed it from the default
+    /// template (step 1 of the two-step spawn flow). Creating it is the
+    /// whole of this step — tailoring what the template seeded is not a
+    /// separate mechanism, it's a `MergeConfigPr` like every later
+    /// change.
     InitConfig,
     /// Run `nix flake update [inputs...]` on the meta flake and commit
     /// the resulting lock changes.