feature-flags

# Feature Flags Feature flags gate experimental functionality behind user-configurable settings, enabling safe rollout (default off), user opt-in, and easy rollback. ## Checking Feature State ```go import "github.com/marcus/sidecar/internal/features" if features.IsEnabled("tmux_interactive_input") { // Feature-gated code } ``` ## Adding a New Feature Flag 1. Define the feature in `internal/features/features.go`: ```go var MyNewFeature = Feature{ Name: "my_new_feature", Default: false, Description: "Description of what this enables", } ``` 2. Add to the `allFeatures` slice: ```go var allFeatures = []Feature{ TmuxInteractiveInput, MyNewFeature, // Add here } ``` 3. Use the feature check in your code: ```go if features.IsEnabled("my_new_feature") { // New functionality } ``` ## User Configuration ### Config file (`~/.config/sidecar/config.json`) ```json { "features": { "flags": { "tmux_interactive_input": true } } } ``` ### CLI override (takes precedence over config) ```bash sidecar --enable-feature=tmux_interactive_input sidecar --disable-feature=tmux_interactive_input sidecar --enable-feature=feature1,feature2 # Multiple features ``` Unknown feature names in CLI flags produce a warning but do not prevent startup. ## Priority Order Feature state resolves in this order (first match wins): 1. CLI override (`--enable-feature`, `--disable-feature`) 2. Config file (`features.flags` in config.json) 3. Defau...