fix(tui): reference inferred hues in migrated themes

[jlongster]

Summary

• replace migrated V1 token hex values with exact generated hue references where possible
• make V1 accent and primary own their inferred base hue scales and alias accent/interactive to those hues
• prefer primary when accent and primary infer the same hue

Tests

• bun test test/theme/v2
• bun typecheck
• bunx prettier --check packages/tui/src/theme/v2/v1-migrate.ts packages/tui/test/theme/v2/v1-migrate.test.ts