feat: chat cli UI revamp prep (#3112)

* creates crate for new UI layer

* defines protocol types according to agui

* defines conduit constructs

* initial conduit integration with old loop

* adjusts spinners to be compatible with conduit

* adds mvp for new ui layer

* adds settings for different UI mode

* adds content extraction logic for legacy mode

* instruments tool call to emit structured message

* hides cursor during spinner

* instruments assistant text to emit structured events

* handles tool call rejection structured event

* flushes stderr and stdout accordingly to old behavior

Author: dingfeli

Cargo.lock

@@ -1,6 +1,6 @@
 [workspace]
 resolver = "3"
-members = ["crates/amzn-codewhisperer-client", "crates/amzn-codewhisperer-streaming-client", "crates/amzn-consolas-client", "crates/amzn-qdeveloper-streaming-client", "crates/amzn-toolkit-telemetry-client", "crates/aws-toolkit-telemetry-definitions", "crates/chat-cli", "crates/semantic-search-client"]
+members = ["crates/amzn-codewhisperer-client", "crates/amzn-codewhisperer-streaming-client", "crates/amzn-consolas-client", "crates/amzn-qdeveloper-streaming-client", "crates/amzn-toolkit-telemetry-client", "crates/aws-toolkit-telemetry-definitions", "crates/chat-cli", "crates/semantic-search-client", "crates/chat-cli-ui"]
 default-members = ["crates/chat-cli"]
 
 [workspace.package]
@@ -132,6 +132,7 @@ schemars = "1.0.4"
 jsonschema = "0.30.0"
 zip = "2.2.0"
 rmcp = { version = "0.8.0", features = ["client", "transport-sse-client-reqwest", "reqwest", "transport-streamable-http-client-reqwest", "transport-child-process", "tower", "auth"] }
+chat-cli-ui = { path = "crates/chat-cli-ui" }
 
 [workspace.lints.rust]
 future_incompatible = "warn"

Cargo.toml

@@ -0,0 +1,40 @@
+[package]
+name = "chat-cli-ui"
+authors.workspace = true
+edition.workspace = true
+homepage.workspace = true
+publish.workspace = true
+version.workspace = true
+license.workspace = true
+
+[lints]
+workspace = true
+
+[dependencies]
+tracing.workspace = true
+tracing-appender.workspace = true
+tracing-subscriber.workspace = true
+thiserror.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+chrono.workspace = true
+crossterm.workspace = true
+tokio.workspace = true
+eyre.workspace = true
+tokio-util.workspace = true
+futures.workspace = true
+ratatui = "0.29.0"
+
+[target.'cfg(unix)'.dependencies]
+nix.workspace = true
+skim.workspace = true
+
+[target.'cfg(target_os = "macos")'.dependencies]
+objc2.workspace = true
+objc2-app-kit.workspace = true
+objc2-foundation.workspace = true
+security-framework.workspace = true
+
+[target.'cfg(windows)'.dependencies]
+windows.workspace = true
+winreg.workspace = true