feat: add runtime resource snapshots

crates/fabric-core/src/error.rs

@@ -335,6 +335,26 @@ pub enum FabricError {
         /// Environment handle id.
         environment_id: String,
     },
+    /// A runtime's resources cannot be read now: the runtime stopped, is
+    /// stopping, its adapter host process exited, a live process in its tree
+    /// or the process table cannot be read, or the process tree kept changing
+    /// during the read.
+    #[error("resource observation is unavailable for runtime `{runtime_id}`: {reason}")]
+    ResourceObservationUnavailable {
+        /// Runtime handle id.
+        runtime_id: String,
+        /// Why the runtime cannot be observed.
+        reason: String,
+    },
+    /// The runtime's adapter kind, environment provider, or operating system has
+    /// no resource reader.
+    #[error("resource observation is unsupported for runtime `{runtime_id}`: {reason}")]
+    ResourceObservationUnsupported {
+        /// Runtime handle id.
+        runtime_id: String,
+        /// What has no resource reader.
+        reason: String,
+    },
     /// Process adapter settings were invalid.
     #[error("invalid process adapter settings for {path}: {source}")]
     InvalidProcessSettings {

crates/fabric-core/src/lib.rs

@@ -10,9 +10,11 @@ pub mod config;
 pub mod doctor;
 mod environment;
 pub mod error;
+pub mod resource_snapshot;
 pub mod runtime;
 pub mod schema;
 mod task_command;
+mod time;
 
 pub use adapter_contract::{ADAPTER_CONTRACT_VERSION, AdapterExtensionPoint};
 pub use agent_execution::{
@@ -40,6 +42,7 @@ pub use config::{
 };
 pub use doctor::{DoctorCheck, DoctorReport, DoctorStatus, doctor_plan};
 pub use error::{FabricError, Result};
+pub use resource_snapshot::RuntimeResourceSnapshot;
 pub use runtime::{
     AdapterInvocation, ArtifactManifest, ArtifactRef, EnvironmentHandle, EnvironmentReference,
     ErrorInfo, ErrorStage, FabricEvent, InvocationHandle, OpenAiChatCompletionChunk,
@@ -49,8 +52,8 @@ pub use runtime::{
     RunRequest, RunResult, RunStatus, RunUsage, RuntimeContext, RuntimeHandle,
     RuntimeTelemetryContext, ServiceHandle, ServiceOwnership, ServiceReference, TelemetryRef,
     attach_environment, attach_service, invoke_openai_stream, invoke_runtime, prepare_environment,
-    prepare_service, release_environment, release_service, run_plan, start_runtime,
-    start_runtime_in, start_runtime_with_service, stop_runtime,
+    prepare_service, release_environment, release_service, run_plan, runtime_resource_snapshot,
+    start_runtime, start_runtime_in, start_runtime_with_service, stop_runtime,
 };
 pub use schema::{
     SchemaName, generate_all_schemas, generate_schema, generate_schema_json, write_schema_snapshots,