Adds switchable model profiles (quality/balanced/budget) to control
which Claude model each agent uses, balancing quality vs token spend.
New files:
- get-shit-done/references/model-profiles.md - profile lookup table
- commands/gsd/set-profile.md - runtime profile switching
Updated orchestrators to resolve model before spawning agents:
- new-project, new-milestone (7 calls each)
- plan-phase (4 calls)
- execute-phase (3 calls)
- audit-milestone, debug, research-phase, quick (1-2 calls each)
- workflows: execute-phase, execute-plan, verify-work, map-codebase
Profile stored in .planning/config.json as model_profile.
Default: "balanced" (Opus for planning, Sonnet for execution).
Closes#160
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>