Feat v0.9.4 package adoption + roles

Packages can declare `adoptable: true` in their manifest. When a team
adopts an adoptable package, a team-scoped copy is created that references
the original via `adopted_from` (shared assets, no disk duplication).
The package's `requires_roles` auto-populate into a new `team_role_catalog`
table so team admins know which roles to assign.

Migration 017: adoptable/adopted_from columns on packages, team_role_catalog
table. 4 new endpoints (adopt, list adoptable, unadopt, role catalog).
AdoptTeamWorkflow deprecated. 11 new tests, all passing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/handlers/package_validate.go

@@ -34,6 +34,7 @@ type ManifestInfo struct {
 	UserPermissions []string // user-facing permissions declared by the extension
 	GatePermission  string   // if set, checks this user permission before calling on_request
 	RequiresRoles   []string // team roles needed to access this package (advisory, OR semantics)
+	Adoptable       bool     // if true, teams can adopt this package to get a team-scoped copy
 }
 
 // ValidateManifest parses a manifest map and validates all required fields,
@@ -178,6 +179,11 @@ func ValidateManifest(manifest map[string]any) (*ManifestInfo, error) {
 		}
 	}
 
+	// v0.9.4: adoptable — teams can adopt this package to get a team-scoped copy
+	if v, ok := manifest["adoptable"].(bool); ok {
+		info.Adoptable = v
+	}
+
 	info.SchemaVersion = ParseSchemaVersion(manifest)
 
 	// ── Type-specific constraints ────────────────────────────────
@@ -216,10 +222,16 @@ func ValidateManifest(manifest map[string]any) (*ManifestInfo, error) {
 		if info.HasRoute {
 			return nil, fmt.Errorf("library packages cannot have a route")
 		}
+		if info.Adoptable {
+			return nil, fmt.Errorf("library packages cannot be adoptable")
+		}
 	case "test-runner":
 		// Test runners are surface-like packages discovered by type.
 		// They are not shown in navigation (extensionNavItems filters for surface/full).
 		// They may have a route but it's optional — the registry surface provides access.
+		if info.Adoptable {
+			return nil, fmt.Errorf("test-runner packages cannot be adoptable")
+		}
 	}
 
 	return info, nil