fix: support Agent tool for sub-agent visualization

[erichprates]

The Agent tool (used by Claude Code's Task tool invocations) was not being visualized as a sub-agent character in the Pixel Agents office.

Three changes in transcriptParser.ts:

1. Add 'Agent' to PERMISSION_EXEMPT_TOOLS so it does not trigger the false permission-wait heuristic while the sub-agent is running.

2. Add case 'Agent': before case 'Task': in formatToolStatus so the status string starts with "Subtask: ". The webview checks for this prefix to call addSubagent() and spawn a new pixel character linked to the parent agent.

3. Include 'Agent' in the subagentClear guard so the spawned character is correctly despawned when the Agent tool completes.

[drewf]

I independently found the same issue and submitted a similar fix in #76. My PR also covers a 4th location that this one is missing: the progress record handler in processProgressRecord() (~line 207) that validates the parent tool name. Without that fix, sub-agent progress records (tool activity within sub-agents) are silently ignored for the Agent tool.

Happy to close mine if this one adds that 4th fix, or the maintainer can pick whichever.

[florintimbuc]

Hey @erichprates, thanks for catching this and for the clear write-up, great fix :)
This has been fully addressed in our v1.1.0 release (merged via #122), we added 'Agent' to all the same places you identified, plus the 4th location that @drewf pointed out in the progress record handler.

@drewf, thanks for flagging that extra spot, it should be included as well

Closing as superseded, appreciate the contributions from both of you!