Name the paths a seat's holder owns, and refuse a claim or a declaration without the seat (issue 412)

Which module owns /etc/hosts or /etc/resolv.conf on a machine was answered only by reading every
manifest, and a module not holding node-hostname could declare /etc/hosts where nobody held it.
hq ADR 0287 makes the paths part of the seat's definition: node-hostname names /etc/hosts and
/etc/hostname, node-uplink names /etc/resolv.conf stepping back for node-resolver, node-resolver
names /etc/resolv.conf.

CanHold refuses a holder that does not declare every path (registration and handover), registration
refuses a module declaring a seat's path while claiming none of the seats naming it, a module's own
seat names paths under the same rules (node only, literal, not named by another seat), composition
refuses a generated resource on a seat's path, the uplink's step-back is read from the seat instead
of a special case, and `seats` shows each seat's paths and who owns each on each machine.

internal/catalogue/seats_declared.go

@@ -67,6 +67,10 @@ type SeatDeclaration struct {
 	// Records are state buckets of the declaring module that each user reads under its own name — the
 	// keys `<user>.…` and no other (ADR 0259 §3).
 	Records []string `json:"records,omitempty"`
+	// Paths are the paths on its machine the seat's holder owns (novox/hq ADR 0287), under the rules the
+	// mesh's own seats name theirs by: a node seat only, each absolute and literal, and none another seat
+	// names. A module's seat never steps back.
+	Paths []string `json:"paths,omitempty"`
 }
 
 // KindedBenches are the seats that may be kinded (novox/hq ADR 0234 §2): `channel` sends to the operator,
@@ -163,6 +167,7 @@ func declaredSeatProblems(m Manifest) []string {
 			}
 		}
 		problems = append(problems, trafficProblems(m, s)...)
+		problems = append(problems, declaredSeatPathProblems(m, s)...)
 	}
 
 	for _, u := range m.Uses {
@@ -271,6 +276,10 @@ func CatalogueProblems(shelf Shelf) []string {
 		return ok
 	}
 
+	// Which seats name each path (novox/hq ADR 0287): a module's seat naming one another seat names loses.
+	named, pathProblems := pathSeats(shelfOrder(shelf), shelf, declaredBy)
+	problems = append(problems, pathProblems...)
+
 	// Who claims each kind of a kinded bench, so a second claim of one kind is refused (ADR 0234 §2).
 	kindsTaken := map[string]string{}
 
@@ -327,7 +336,15 @@ func CatalogueProblems(shelf Shelf) []string {
 					"%s claims %s but does not serve %s, which that seat's protocol promises",
 					module, c.Name, strings.Join(missing, ", ")))
 			}
+			// And owns what the seat's holder owns, as a holder of the mesh's own seats does (ADR 0287).
+			if missing := missingPaths(m, asSeatPaths(s.Paths)); len(missing) > 0 {
+				problems = append(problems, fmt.Sprintf(
+					"%s claims %s but does not declare %s, which that seat's holder owns (novox/hq ADR 0287)",
+					module, c.Name, strings.Join(missing, ", ")))
+			}
 		}
+		// Only a claimant declares a seat's path (novox/hq ADR 0287).
+		problems = append(problems, unclaimedSeatPaths(m, named)...)
 	}
 	// **A trusted holder runs as its own account** (novox/hq ADR 0259 §8): a module saying warrants, or
 	// speaking for a kind that proves its sender, is never carried by a machine's runtime.