feat: add Copilot CLI resume support to session dropdown

[MCBoarder289]

This is simply adding copilot support for the resume session dropdown.

Here's what all changed and is mentioned in the commit message:

• Add "copilot" to resumeAgents map with command template "copilot --resume=%s"
• Add RESUME_AGENTS["copilot"] to frontend resume.ts
• Update readSessionCwd to also extract cwd from data.context.cwd, matching the Copilot session.start JSONL format
• Update resume_handler_test: replace copilot unsupported test with a passing copilot command_only test; use cursor for unsupported case
• Update resume.test.ts: mark copilot as supported, add copilot command generation test
• Add TestReadSessionCwd_CopilotFormat for the data.context.cwd path

[roborev-ci]

roborev: Combined Review (00fde4a)

Summary Verdict: The commit adding Copilot CLI resume support is clean and safe, with no medium, high, or critical issues found.

All agents agree the code is clean.

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Synthesized from 3 reviews (agents: codex, gemini | types: default, security)

[roborev-ci]

roborev: Combined Review (d4fee72)

Summary: The PR successfully adds Copilot session resume support, but introduces a medium severity issue regarding hardcoded launcher commands.

Medium

• Hardcoded copilot launcher command will fail for GitHub CLI users
  The
  new command templates in frontend/src/lib/utils/resume.ts:10 and [internal/server/resume.go](/home/robore
  v/.roborev/clones/wesm/agentsview/internal/server/resume.go):46 assume a standalone copilot binary is on PATH. On setups that only expose Copilot through the GitHub CLI shim, gh copilot is available and its help explicitly says Copilot flags/
  args must be passed after --. In that common setup, the new resume button will copy/launch a command that simply does not exist.
  Suggested fix: Resolve the launcher dynamically on the backend, preferring copilot when present and otherwise emitting a gh copilot -- ... form, then avoid hardcoding a
  separate frontend fallback for Copilot.

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Synthesized from 3 reviews (agents: codex, gemini | types: default, security)

[roborev-ci]

roborev: Combined Review (e28dec0)

Summary: The PR successfully implements Copilot CLI resume support but introduces a CI coverage gap by narrowing path filters in the desktop artifacts workflow.

Medium

• [.github/workflows/desktop-artifacts.yml:6](/home/roborev/.roborev/clones
  /wesm/agentsview/.github/workflows/desktop-artifacts.yml)
  Removing cmd/** and internal/** from the pull_request.paths filter creates a regression in desktop CI coverage. The desktop artifact job builds and packages a Go sidecar from ./cmd/agentsview and its dependencies under internal/**. With this change, a backend-only PR can break the desktop build or packaging without triggering the workflow.
  Suggested fix: Restore the backend-triggering paths to the filter (at minimum cmd/agentsview/** and relevant internal/** paths), or replace
  the path filter with a dependency-aware trigger to ensure any change affecting the bundled sidecar runs the desktop artifact job.

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Synthesized from 3 reviews (agents: codex, gemini | types: default, security)