feat(cli): add nemo-flow plugins edit

crates/cli/Cargo.toml

@@ -23,6 +23,7 @@ axum = "0.8"
 bytes = "1"
 clap = { version = "4", features = ["derive", "env"] }
 clap_complete = "4"
+console = "0.16"
 futures-util = "0.3"
 http = "1"
 http-body-util = "0.1"

crates/cli/README.md

@@ -103,19 +103,30 @@ Project config lives at `./.nemo-flow/config.toml`; user config lives at
 The project layer overrides system config, and the user layer overrides the
 project layer.
 
-Exporter config uses nested per-backend tables:
+Observability exporters are configured through the plugin config. Edit the user
+plugin config with:
+
+```bash
+nemo-flow plugins edit
+```
+
+The canonical plugin file is `plugins.toml`; user config lives at
+`~/.config/nemo-flow/plugins.toml` or
+`$XDG_CONFIG_HOME/nemo-flow/plugins.toml`. Project config lives at
+`.nemo-flow/plugins.toml`.
+
+Minimal ATIF example:
 
 ```toml
-[exporters.atif]
-dir = "./atif"
+version = 1
 
-[exporters.atof]
-dir = "./atof"
-mode = "append"
-filename_template = "{session_id}.jsonl"
+[[components]]
+kind = "observability"
+enabled = true
 
-[exporters.openinference]
-endpoint = "http://localhost:6006/v1/traces"
+[components.config.atif]
+enabled = true
+output_directory = "./atif"
 ```
 
 ## Documentation