## ADDED Requirements

### Requirement: Bounded display mode contract
The Protocol SHALL define `DisplayMode` with required integer
`resolution_width` from 320 through 16384, `resolution_height` from 200 through
8640, and `fps` from 1 through 240, rejecting missing, unknown, or out-of-range
fields.

#### Scenario: Valid display mode
- **WHEN** a client encodes a 2560 by 1440 display mode at 120 FPS
- **THEN** generated Go, Rust, and Swift bindings accept the same exact values.

#### Scenario: Invalid display mode
- **WHEN** any dimension or FPS is outside its bound or an unknown field exists
- **THEN** strict Protocol validation rejects the object.

### Requirement: Feature-gated optional display disclosure
`SessionRequest.requested_display_mode`,
`BrokerSession.requested_display_mode`,
`BrokerSession.effective_display_mode`, and `ManifestProfile.display_mode`
SHALL be optional references to `DisplayMode`. Go bindings SHALL use pointers
with JSON omission and Rust/Swift bindings SHALL use optionals. A client MUST
send the request only after `display.request.v1` negotiation, and a
display-aware manifest MUST contain the accepted mode. Legacy requests SHALL
produce legacy response shapes without these fields.

#### Scenario: Legacy request remains unchanged
- **WHEN** a client omits `requested_display_mode`
- **THEN** encoding omits the field and compatible Server responses omit all
  display-mode fields.

#### Scenario: Display-aware request discloses acceptance
- **WHEN** a negotiated client sends a valid requested mode
- **THEN** session responses preserve the requested mode and the allocated
  manifest includes the Server-accepted mode.