feat: add github copilot cli integration (#386)

* feat: add github copilot cli integration

refs #232

* docs: restore 0.6.5 changelog and document copilot hook flow

* test: cover copilot camelcase hook payloads

---------

Co-authored-by: Ogulcan Celik <ogulcancelik@gmail.com>

5 files changed, 24 insertions, 4 deletions

diff --git a/docs/next/website/src/content/docs/agents.mdx b/docs/next/website/src/content/docs/agents.mdx
index bc540198..57d18b0e 100644
--- a/docs/next/website/src/content/docs/agents.mdx
+++ b/docs/next/website/src/content/docs/agents.mdx
@@ -58,6 +58,7 @@ herdr integration install pi
 herdr integration install omp
 herdr integration install claude
 herdr integration install codex
+herdr integration install copilot
 herdr integration install opencode
 herdr integration install hermes
 herdr integration install qodercli
diff --git a/docs/next/website/src/content/docs/cli-reference.mdx b/docs/next/website/src/content/docs/cli-reference.mdx
index ad837142..383107cf 100644
--- a/docs/next/website/src/content/docs/cli-reference.mdx
+++ b/docs/next/website/src/content/docs/cli-reference.mdx
@@ -207,6 +207,7 @@ herdr integration install pi
 herdr integration install omp
 herdr integration install claude
 herdr integration install codex
+herdr integration install copilot
 herdr integration install opencode
 herdr integration install hermes
 herdr integration install qodercli
@@ -214,6 +215,7 @@ herdr integration uninstall pi
 herdr integration uninstall omp
 herdr integration uninstall claude
 herdr integration uninstall codex
+herdr integration uninstall copilot
 herdr integration uninstall opencode
 herdr integration uninstall hermes
 herdr integration uninstall qodercli
diff --git a/docs/next/website/src/content/docs/configuration.mdx b/docs/next/website/src/content/docs/configuration.mdx
index 1a47a6c1..4074d791 100644
--- a/docs/next/website/src/content/docs/configuration.mdx
+++ b/docs/next/website/src/content/docs/configuration.mdx
@@ -380,7 +380,7 @@ Herdr can restart supported agent panes in their native conversation sessions af
 resume_agents_on_restore = true
 ```
 
-This is enabled by default. Herdr only resumes panes that reported a native session reference through an official Herdr integration. Supported resume targets are Claude Code, Codex, Pi, Hermes Agent, and OpenCode. Unsupported, missing, invalid, duplicated, or stale session references restore as a normal shell in the saved pane directory.
+This is enabled by default. Herdr only resumes panes that reported a native session reference through an official Herdr integration. Supported resume targets are Claude Code, Codex, GitHub Copilot CLI, Pi, Hermes Agent, and OpenCode. Unsupported, missing, invalid, duplicated, or stale session references restore as a normal shell in the saved pane directory.
 
 Session references are stored in the local Herdr session snapshot. They are not shown in normal pane, agent, status, or event output.
 
diff --git a/docs/next/website/src/content/docs/integrations.mdx b/docs/next/website/src/content/docs/integrations.mdx
index f1d7d83e..2cf87e12 100644
--- a/docs/next/website/src/content/docs/integrations.mdx
+++ b/docs/next/website/src/content/docs/integrations.mdx
@@ -1,6 +1,6 @@
 ---
 title: Integrations
-description: Install Herdr integrations for Pi, OMP, Claude Code, Codex, OpenCode, Hermes Agent, and Qoder CLI.
+description: Install Herdr integrations for Pi, OMP, Claude Code, Codex, GitHub Copilot CLI, OpenCode, Hermes Agent, and Qoder CLI.
 ---
 
 Herdr detects supported agents automatically. Integrations make that detection more precise by reporting semantic state directly to Herdr.
@@ -16,6 +16,7 @@ herdr integration install pi
 herdr integration install omp
 herdr integration install claude
 herdr integration install codex
+herdr integration install copilot
 herdr integration install opencode
 herdr integration install hermes
 herdr integration install qodercli
@@ -28,6 +29,7 @@ herdr integration uninstall pi
 herdr integration uninstall omp
 herdr integration uninstall claude
 herdr integration uninstall codex
+herdr integration uninstall copilot
 herdr integration uninstall opencode
 herdr integration uninstall hermes
 herdr integration uninstall qodercli
@@ -45,9 +47,9 @@ Herdr combines three signals:
 
 Integrations enrich state reporting. They do not replace process detection.
 
-Some integrations also report native agent session references. Herdr uses official session references to resume Claude Code, Codex, Pi, Hermes Agent, and OpenCode panes after a Herdr server restart unless `[session] resume_agents_on_restore = false` disables it.
+Some integrations also report native agent session references. Herdr uses official session references to resume Claude Code, Codex, GitHub Copilot CLI, Pi, Hermes Agent, and OpenCode panes after a Herdr server restart unless `[session] resume_agents_on_restore = false` disables it.
 
-Native session restore requires current Herdr integrations: Pi integration version `2`, Claude Code version `4`, Codex version `4`, OpenCode version `2`, or Hermes Agent version `2`. OMP integration version `2` reports agent state only. Check installed versions with `herdr integration status`.
+Native session restore requires current Herdr integrations: Pi integration version `2`, Claude Code version `4`, Codex version `4`, GitHub Copilot CLI version `1`, OpenCode version `2`, or Hermes Agent version `2`. OMP integration version `2` reports agent state only. Check installed versions with `herdr integration status`.
 
 ## Pi
 
@@ -107,6 +109,20 @@ Codex state is reported through the same local socket API used by other integrat
 
 Herdr uses `~/.codex` by default, or `CODEX_HOME` when set. The Codex config directory must already exist. Install writes `herdr-agent-state.sh`, updates `hooks.json`, and ensures `[features] hooks = true` in `config.toml`. It also removes the deprecated top-level `codex_hooks` flag when present. Uninstall removes Herdr entries from `hooks.json` and deletes the hook script, but leaves `config.toml` unchanged.
 
+## GitHub Copilot CLI
+
+Install the GitHub Copilot CLI hook:
+
+```bash
+herdr integration install copilot
+```
+
+Copilot state is reported through the same local socket API used by other integrations.
+
+Herdr uses `~/.copilot` by default, or `COPILOT_HOME` when set. The Copilot config directory must already exist. Install writes `hooks/herdr-agent-state.sh` and updates `settings.json` with Herdr hook entries. The hook maps prompt submission, tool use, post-tool progress after approvals, `ask_user` prompts, `exit_plan_mode` plan review prompts, permission notifications, agent idle notifications, turn stops, and session exits into Herdr state. Uninstall removes Herdr entries from `settings.json` and deletes the hook script.
+
+After Copilot emits a session-bearing event, Herdr can use the reported session id to resume the pane with `copilot --resume=<id>`.
+
 ## OpenCode
 
 Install the OpenCode plugin:
diff --git a/docs/next/website/src/content/docs/session-state.mdx b/docs/next/website/src/content/docs/session-state.mdx
index bfb62ef5..0b919903 100644
--- a/docs/next/website/src/content/docs/session-state.mdx
+++ b/docs/next/website/src/content/docs/session-state.mdx
@@ -56,6 +56,7 @@ Native session restore requires these Herdr integration versions or newer:
 | Pi | `2` | `pi --session <path-or-id>` |
 | Claude Code | `4` | `claude --resume <id>` |
 | Codex | `4` | `codex resume <id>` |
+| GitHub Copilot CLI | `1` | `copilot --resume=<id>` |
 | OpenCode | `2` | `opencode --session <id>` |
 | Hermes Agent | `2` | `hermes --resume <id>` |