[upstream-sync] Port changes from copilot-sdk: COPILOT_CLI_PATH support and new session event type

CHANGELOG.md

@@ -2,6 +2,16 @@
 All notable changes to this project will be documented in this file. This change log follows the conventions of [keepachangelog.com](http://keepachangelog.com/).
 
 ## [Unreleased]
+### Changed (v0.2.0 sync)
+- **`COPILOT_CLI_PATH` env var support** — when `:cli-path` is not explicitly provided to `client`, the
+  SDK now checks the `COPILOT_CLI_PATH` environment variable (from the user-supplied `:env` map first,
+  then the process environment). This aligns with the Node.js SDK behavior. Explicit `:cli-path` takes
+  precedence; falls back to `"copilot"` from PATH when the env var is not set (upstream PR #925).
+- **New `session.custom_agents_updated` event type** — added to `::event-type` spec. Emitted when custom
+  agents are loaded or reloaded; data includes `agents`, `warnings`, and `errors` fields (upstream PR #916).
+- **Extended sub-agent event data** — `subagent.completed` and `subagent.failed` events now carry optional
+  fields `model`, `total-tool-calls`, `total-tokens`, and `duration-ms`. `skill.completed` events now
+  carry an optional `description` field. These are passed through as-is in event data maps (upstream PR #916).
 
 ## [0.2.0.0] - 2026-03-23
 ### Added (v0.2.0 sync)

src/github/copilot_sdk/client.clj

@@ -119,7 +119,7 @@
   "Create a new CopilotClient.
 
    Options:
-   - :cli-path      - Path to CLI executable (default: \"copilot\")
+   - :cli-path      - Path to CLI executable (default: COPILOT_CLI_PATH env var, or \"copilot\" from PATH)
    - :cli-args      - Extra arguments for CLI
    - :cli-url       - URL of existing server (e.g., \"localhost:8080\")
    - :cwd           - Working directory for CLI process
@@ -183,6 +183,13 @@
          opts-with-defaults (cond-> opts
                               (and (:github-token opts) (nil? (:use-logged-in-user? opts)))
                               (assoc :use-logged-in-user? false))
+         ;; Resolve COPILOT_CLI_PATH: check user :env map first, then system env.
+         ;; Applied only when :cli-path is not explicitly set and :cli-url is not set.
+         env-cli-path (when (and (nil? (:cli-path opts)) (nil? (:cli-url opts)))
+                        (or (get (:env opts) "COPILOT_CLI_PATH")
+                            (System/getenv "COPILOT_CLI_PATH")))
+         opts-with-defaults (cond-> opts-with-defaults
+                              env-cli-path (assoc :cli-path env-cli-path))
          merged (merge (default-options) opts-with-defaults)
          child-process? (:is-child-process? opts)
          cli-url? (boolean (:cli-url opts))

src/github/copilot_sdk/specs.clj

@@ -515,7 +515,8 @@
     ;; Session status events
     :copilot/session.tools_updated :copilot/session.background_tasks_changed
     :copilot/session.skills_loaded :copilot/session.mcp_servers_loaded
-    :copilot/session.mcp_server_status_changed :copilot/session.extensions_loaded})
+    :copilot/session.mcp_server_status_changed :copilot/session.extensions_loaded
+    :copilot/session.custom_agents_updated})
 
 ;; Session events
 (s/def ::already-in-use? boolean?)