rename OLLIE_9MOUNT → OLLIE; always inject OLLIE into execute env

$OLLIE is the ollie root (FUSE mount). Renaming makes it shorter and
cleaner for use in sandboxed code. SetSessionID now resolves and
injects OLLIE into the execute server env so it is always available
regardless of whether the parent process has it set.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/sandbox/config.go

@@ -86,7 +86,7 @@ func DefaultConfig() *Config {
 			},
 			RWX: []string{
 				"{HOME}/.config/ollie",
-				"{OLLIE_9MOUNT}",
+				"{OLLIE}",
 				"{HOME}/mnt/ollie",
 			},
 		},
@@ -103,7 +103,7 @@ func DefaultConfig() *Config {
 			"LANG",
 			"TERM",
 			"OLLIE_SESSION_ID",
-			"OLLIE_9MOUNT",
+			"OLLIE",
 			"OLLIE_MEMORY_PATH",
 		},
 		Advanced: AdvancedConfig{
@@ -350,7 +350,7 @@ func SystemDefaults() LayeredConfig {
 			"LANG",
 			"TERM",
 			"OLLIE_SESSION_ID",
-			"OLLIE_9MOUNT",
+			"OLLIE",
 		},
 	}
 }

pkg/agent/core.go

@@ -359,6 +359,13 @@ func (s *agentCore) SetSessionID(newID string) error {
 		if srv, ok := s.dispatcher.GetServer("execute"); ok {
 			if es, ok := srv.(tools.EnvSetter); ok {
 				es.SetEnv("OLLIE_SESSION_ID", newID)
+				// Ensure OLLIE is always set, resolving the default if unset.
+				ollie := os.Getenv("OLLIE")
+				if ollie == "" {
+					home, _ := os.UserHomeDir()
+					ollie = home + "/mnt/ollie"
+				}
+				es.SetEnv("OLLIE", ollie)
 			}
 		}
 	}
@@ -959,7 +966,7 @@ func (s *agentCore) handleCommand(ctx context.Context, input string, handler Eve
 		if cmd == "/tools" {
 			subdir = "t"
 		}
-		mount := os.Getenv("OLLIE_9MOUNT")
+		mount := os.Getenv("OLLIE")
 		if mount == "" {
 			home, _ := os.UserHomeDir()
 			mount = home + "/mnt/ollie"