feat(agents): add GitHub Copilot CLI as a code-agent option (#28)

* feat(agents): add GitHub Copilot CLI as a code-agent option

Wire `copilot -p "..." --allow-all-tools` into AGENT_DEFS so the daemon
can spawn it alongside the other CLIs. `--allow-all-tools` is required
in non-interactive mode (same tradeoff as Claude's `-p` and Codex's
`exec`). Add a matching GitHub-dark icon with the Copilot two-eye mark.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* fix(copilot-stream): treat result.success as completed when exitCode missing

Strict `obj.exitCode === 0 ? 'completed' : 'error'` mis-flags turns
where Copilot emits a `result` event with `success: true` but no numeric
exitCode. Switch to `obj.success === true || obj.exitCode === 0`. The
asymmetry argument that applies to other defensive ideas in this file
(raw fallback, stringifyResult cap) doesn't apply here — Claude's
`result` event uses a string `stop_reason`, not exitCode, so this is a
Copilot-specific schema-variance fix rather than a one-sided hardening.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs(agent-adapters): list Copilot CLI auth paths in §5.7

Adds a one-line note: detection assumes Copilot is already
authenticated, via either `copilot login` (subcommand, OAuth device
flow) or the interactive `/login` slash command inside `copilot` with
no args. Surfaces the assumption so anyone hitting an undetected /
unversioned Copilot install can trace it back.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/AgentIcon.tsx

@@ -108,6 +108,23 @@ const VISUALS: Record<string, Visual> = {
       );
     },
   },
+  // GitHub Copilot — GitHub-dark with the Copilot two-eye mark.
+  copilot: {
+    bg: 'linear-gradient(135deg, #0d1117 0%, #1f2937 100%)',
+    fg: '#ffffff',
+    glyph: (s) => {
+      const c = s / 2;
+      const eyeOff = s * 0.14;
+      const eyeRx = s * 0.075;
+      const eyeRy = s * 0.12;
+      return (
+        <g fill="#ffffff">
+          <ellipse cx={c - eyeOff} cy={c} rx={eyeRx} ry={eyeRy} />
+          <ellipse cx={c + eyeOff} cy={c} rx={eyeRx} ry={eyeRy} />
+        </g>
+      );
+    },
+  },
   // Qwen — Alibaba indigo with stylized Q.
   qwen: {
     bg: 'linear-gradient(135deg, #615ced 0%, #8b5cf6 100%)',

src/i18n/locales/en.ts

@@ -64,7 +64,7 @@ export const en: Dict = {
   'settings.rescan': '↻ Rescan',
   'settings.rescanTitle': 'Re-scan PATH',
   'settings.noAgentsDetected':
-    'No agents detected yet. Install one of Claude Code, Codex, Gemini CLI, OpenCode, Cursor Agent, or Qwen, then click Rescan.',
+    'No agents detected yet. Install one of Claude Code, Codex, Gemini CLI, OpenCode, Cursor Agent, Qwen, or GitHub Copilot CLI, then click Rescan.',
   'settings.apiSection': 'Anthropic API',
   'settings.apiKey': 'API key',
   'settings.showKey': 'Show key',

src/i18n/locales/zh-CN.ts

@@ -63,7 +63,7 @@ export const zhCN: Dict = {
   'settings.rescan': '↻ 重新扫描',
   'settings.rescanTitle': '重新扫描 PATH',
   'settings.noAgentsDetected':
-    '尚未检测到任何代理。请安装 Claude Code、Codex、Gemini CLI、OpenCode、Cursor Agent 或 Qwen 中的一个，然后点击「重新扫描」。',
+    '尚未检测到任何代理。请安装 Claude Code、Codex、Gemini CLI、OpenCode、Cursor Agent、Qwen 或 GitHub Copilot CLI 中的一个，然后点击「重新扫描」。',
   'settings.apiSection': 'Anthropic API',
   'settings.apiKey': 'API Key',
   'settings.showKey': '显示 Key',