Add Version field to all Entry structs to fix discovery validation

Issue: After implementing fallback discovery client, dmsg utilities still
failed with "entry validation error: entry has no version" when posting
the local client's entry to HTTP discovery.

Root cause: Multiple places create disc.Entry structs without setting the
Version field. Discovery API requires Version="0.0.1" for all entries.

Fixes:
1. pkg/direct/entries.go - Add Version to GetClientEntry()
2. pkg/direct/client.go - Return ErrKeyNotFound instead of empty Entry
3. internal/cli/cli.go - Add Version to 3 synthetic entries:
   - Discovery server entry (StartDmsgWithSyntheticDiscovery)
   - Discovery server entry (StartDmsgWithDirectClient)
   - Local client entry (StartDmsgWithDirectClient)

The direct client now properly returns ErrKeyNotFound for unknown entries,
allowing the dmsg client to create a new entry with NewClientEntry() which
includes the version field.

Test: dmsg curl -Z and dmsg web -Z now work correctly

Author: Moses Narrow

internal/cli/cli.go

@@ -137,7 +137,8 @@ func StartDmsgWithSyntheticDiscovery(ctx context.Context, dlog *logging.Logger,
 				delegatedServers = append(delegatedServers, server.Static)
 			}
 			syntheticEntry := &disc.Entry{
-				Static: discoveryPK,
+				Version: "0.0.1",
+				Static:  discoveryPK,
 				Client: &disc.Client{
 					DelegatedServers: delegatedServers,
 				},
@@ -310,7 +311,8 @@ func StartDmsgWithDirectClient(ctx context.Context, dlog *logging.Logger, pk cip
 				delegatedServers = append(delegatedServers, server.Static)
 			}
 			discoveryEntry := &disc.Entry{
-				Static: discoveryPK,
+				Version: "0.0.1",
+				Static:  discoveryPK,
 				Client: &disc.Client{
 					DelegatedServers: delegatedServers,
 				},
@@ -326,7 +328,8 @@ func StartDmsgWithDirectClient(ctx context.Context, dlog *logging.Logger, pk cip
 		delegatedServers = append(delegatedServers, server.Static)
 	}
 	clientEntry := &disc.Entry{
-		Static: pk,
+		Version: "0.0.1",
+		Static:  pk,
 		Client: &disc.Client{
 			DelegatedServers: delegatedServers,
 		},

pkg/direct/client.go

@@ -41,7 +41,7 @@ func (c *directClient) Entry(_ context.Context, pubKey cipher.PubKey) (*disc.Ent
 			return entry, nil
 		}
 	}
-	return &disc.Entry{}, nil
+	return nil, disc.ErrKeyNotFound
 }
 
 // PostEntry adds a new Entry to the entries field of directClient.

pkg/direct/entries.go

@@ -16,7 +16,8 @@ func GetClientEntry(pks cipher.PubKeys, servers []*disc.Entry) (clients []*disc.
 
 	for _, pk := range pks {
 		client := &disc.Entry{
-			Static: pk,
+			Version: "0.0.1",
+			Static:  pk,
 			Client: &disc.Client{
 				DelegatedServers: srvPKs,
 			},