Module capability 

CapabilitySet: typed bitfield describing what a buffer can offer. Modes declare what they require via crate::Mode::required_capabilities; the registry validates the buffer satisfies all required bits before activation.

New capabilities are added as the mode system grows. Bit layout is stable once a capability is shipped; a removed capability leaves a hole rather than reusing the bit, so old plugins compiled against the bit don’t accidentally mean something different.

Structs

CapabilitySet

Capabilities a buffer may expose to modes. A mode that requires LSP cannot activate on a text-mode buffer with no LSP attachment; the registry returns crate::ModeActivationError::MissingCapability.