When the adapter type changes via PATCH, the server only preserved
instruction bundle keys (instructionsBundleMode, etc.) from the
existing config. Adapter-agnostic keys like env, cwd, timeoutSec,
graceSec, promptTemplate, and bootstrapPromptTemplate were silently
dropped if the PATCH payload didn't explicitly include them.
This caused env var data loss when adapter type was changed via the
UI or API without sending the full existing adapterConfig.
The fix preserves these adapter-agnostic keys from the existing config
before applying the instruction bundle preservation, matching the
UI's behavior in AgentConfigForm.handleSave.
Co-Authored-By: Paperclip <noreply@paperclip.ing>
ce8d9eb323