Bug

nightshift setup writes provider config fields using Go struct field names (lowercased) instead of the mapstructure tag names. This causes the config to silently break — the fields are written but never read back correctly on subsequent runs.

Root Cause

In cmd/nightshift/commands/setup.go line 1920:

v.Set("providers", cfg.Providers)

When viper serializes a Go struct, it lowercases Go field names rather than using mapstructure tags. So DangerouslySkipPermissions becomes dangerouslyskippermissions in YAML, but the struct expects dangerously_skip_permissions (from mapstructure:"dangerously_skip_permissions").

Affected Fields

Impact

After running nightshift setup:

• dangerously_skip_permissions: true is silently lost — defaults to false
• All tasks fail with permission denials across all iterations, then get abandoned
• Projects are marked "processed today" despite zero work being done
• The config passes nightshift config validate (validation doesn't check field name correctness)
• nightshift config output doesn't display the permission flags at all, making it hard to diagnose

Suggested Fix

Replace the bulk struct set with individual key sets, matching the mapstructure tags:

// Instead of: v.Set("providers", cfg.Providers)
v.Set("providers.claude.enabled", cfg.Providers.Claude.Enabled)
v.Set("providers.claude.data_path", cfg.Providers.Claude.DataPath)
v.Set("providers.claude.dangerously_skip_permissions", cfg.Providers.Claude.DangerouslySkipPermissions)
v.Set("providers.claude.dangerously_bypass_approvals_and_sandbox", cfg.Providers.Claude.DangerouslyBypassApprovalsAndSandbox)
v.Set("providers.codex.enabled", cfg.Providers.Codex.Enabled)
v.Set("providers.codex.data_path", cfg.Providers.Codex.DataPath)
v.Set("providers.codex.dangerously_skip_permissions", cfg.Providers.Codex.DangerouslySkipPermissions)
v.Set("providers.codex.dangerously_bypass_approvals_and_sandbox", cfg.Providers.Codex.DangerouslyBypassApprovalsAndSandbox)
v.Set("providers.preference", cfg.Providers.Preference)

Alternatively, use yaml struct tags alongside mapstructure tags, or use mapstructure.Decode in reverse to produce correct keys.

Reproduction

1. Set correct field names manually in ~/.config/nightshift/config.yaml
2. Run nightshift setup, complete the wizard
3. Inspect config — field names are now wrong
4. Run nightshift run — all tasks fail with permission denials

Environment

• nightshift v0.3.2
• Go module: github.com/marcus/nightshift@v0.3.2
• OS: Linux (Arch)