feat: add Amplitude telemetry for project_created and project_initialized events

[ytallo]

Summary

The Amplitude Metrics PRD requires project_created and project_initialized events to be sent when a user creates a new iii project via iii-tools.

Changes needed

Add a telemetry module to iii-tools (similar to iii/cli/src/telemetry.rs):

• Read/create telemetry_id from ~/.iii/telemetry_id
• Send project_created event at start of project creation
• Send project_initialized event after successful project setup

project_created event properties

{
  "project_id": "<uuid>",
  "project_name": "<directory name>",
  "template": "<quickstart | blank | etc>",
  "language": "<typescript | python | ...>"
}

project_initialized event properties

{
  "project_id": "<uuid>",
  "project_name": "<directory name>",
  "template": "<quickstart | blank | etc>",
  "language": "<typescript | python | ...>",
  "duration_ms": 1234
}

Also: generate project_id (UUID) and project_name and write them to .iii/project.ini in the project root so the engine can pick them up for session telemetry.

Opt-out

Respect III_TELEMETRY_ENABLED=false, CI env var detection, and III_TELEMETRY_DEV=true (same as engine and CLI).

Reference

See iii-hq/amplitude-metrics PRD, section 4a (iii-tools).