The normalizeProviderModelCosts function was only setting { input: 0, output: 0 }
which doesn't match the full OpenCode provider cost shape that includes cache fields.
This fix:
- Preserves existing cost fields (input, output, cache.read, cache.write) if valid
- Adds missing cache: { read: 0, write: 0 } structure when not present
- Validates provider and model objects before modification to avoid poisoning
invalid provider metadata
- Updates ProviderModel type to include optional cache field
Fixes provider cost normalization to maintain cache field compatibility.
Move the Global module from packages/opencode/src/global to packages/core/src/global
to provide a unified location for managing XDG directories and application paths.
This eliminates duplicate path definitions across packages and ensures consistent
access to data, config, cache, state, log, and bin directories throughout the codebase.
