Add custom formations configuration for service worker team generation

[Copilot]

Adds configurable team formation strategies to the CI workflow, enabling different worker organization patterns for build and validation.

Changes

• Workflow dispatch inputs: Manual trigger with formation (standard/parallel/sequential/distributed) and worker_count (1-4) parameters
• Formation environment config: Default strategy, worker roles, and scaling limits
• formation-setup job: Dynamically generates worker matrix based on selected formation strategy
• Enhanced main job: Uses dynamic matrix strategy for parallel execution across workers
• formation-summary job: Reports team generation results to job summary

Formation Strategies

Strategy	Behavior
standard	Single worker handles all tasks
parallel	Multiple workers (builder, validator, deployer) execute simultaneously
sequential	Workers execute in order, passing results
distributed	Tasks split across different runners

Usage

Trigger manually via workflow dispatch or run automatically on push/PR with defaults:

workflow_dispatch:
  inputs:
    formation:
      type: choice
      options: [standard, parallel, sequential, distributed]
    worker_count:
      type: choice
      options: ['1', '2', '3', '4']