chore(deps): remove 8 unused dependencies flagged by cargo-machete (#341)

cargo-machete found 8 direct dependencies that are declared but never
used in the source tree. Removing them tightens the dependency graph
and shrinks Cargo.lock by 40 lines (transitive crate removals where
nothing else pulled them in).

Removed:
- deepseek-core: tokio (the core scaffold doesn't drive any tasks itself)
- deepseek-config: serde_json (TOML-only crate; no JSON serialization)
- deepseek-mcp: deepseek-protocol (proxy boundary doesn't consume protocol types)
- deepseek-app-server: tracing (no tracing! macros in the transport layer)
- deepseek-tui: bytes, csv, deepseek-tui-cli, tokio-stream
  - bytes: no Bytes-typed I/O paths in the TUI
  - csv: agent_swarm/spawn_agents_on_csv removed in #336/#357
  - deepseek-tui-cli: TUI is the runtime, not the dispatcher; no facade calls
  - tokio-stream: futures-util::StreamExt is sufficient for our SSE / mpsc paths

Verified by grep across each crate's `src/` — no `use` of the dep, no
fully-qualified path references. cargo build, cargo clippy -D warnings,
and cargo test continue to pass with the slimmed graph.

Closes #341.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Cargo.lock

@@ -886,27 +886,6 @@ dependencies = [
  "typenum",
 ]
 
-[[package]]
-name = "csv"
-version = "1.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "52cd9d68cf7efc6ddfaaee42e7288d3a99d613d4b50f76ce9827ae0c6e14f938"
-dependencies = [
- "csv-core",
- "itoa",
- "ryu",
- "serde_core",
-]
-
-[[package]]
-name = "csv-core"
-version = "0.1.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "704a3c26996a80471189265814dbc2c257598b96b8a7feae2d31ace646bb9782"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "ctor"
 version = "0.1.26"
@@ -1037,7 +1016,6 @@ dependencies = [
  "serde_json",
  "tokio",
  "tower-http",
- "tracing",
 ]
 
 [[package]]
@@ -1048,7 +1026,6 @@ dependencies = [
  "deepseek-secrets",
  "dirs",
  "serde",
- "serde_json",
  "toml",
  "tracing",
 ]
@@ -1068,7 +1045,6 @@ dependencies = [
  "deepseek-state",
  "deepseek-tools",
  "serde_json",
- "tokio",
  "uuid",
 ]
 
@@ -1100,7 +1076,6 @@ name = "deepseek-mcp"
 version = "0.8.4"
 dependencies = [
  "anyhow",
- "deepseek-protocol",
  "serde",
  "serde_json",
 ]
@@ -1161,16 +1136,13 @@ dependencies = [
  "async-trait",
  "axum",
  "base64",
- "bytes",
  "chrono",
  "clap",
  "clap_complete",
  "colored",
  "crossterm",
- "csv",
  "deepseek-secrets",
  "deepseek-tools",
- "deepseek-tui-cli",
  "dirs",
  "dotenvy",
  "flate2",
@@ -1198,7 +1170,6 @@ dependencies = [
  "thiserror 2.0.17",
  "tiny_http",
  "tokio",
- "tokio-stream",
  "tokio-util",
  "toml",
  "tower-http",
@@ -4593,17 +4564,6 @@ dependencies = [
  "tokio",
 ]
 
-[[package]]
-name = "tokio-stream"
-version = "0.1.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "32da49809aab5c3bc678af03902d4ccddea2a87d028d86392a4b1560c6906c70"
-dependencies = [
- "futures-core",
- "pin-project-lite",
- "tokio",
-]
-
 [[package]]
 name = "tokio-util"
 version = "0.7.18"

crates/app-server/Cargo.toml

@@ -23,4 +23,3 @@ serde.workspace = true
 serde_json.workspace = true
 tokio.workspace = true
 tower-http.workspace = true
-tracing.workspace = true

crates/config/Cargo.toml

@@ -11,6 +11,5 @@ anyhow.workspace = true
 deepseek-secrets = { path = "../secrets", version = "0.8.4" }
 dirs.workspace = true
 serde.workspace = true
-serde_json.workspace = true
 toml.workspace = true
 tracing.workspace = true

crates/core/Cargo.toml

@@ -18,5 +18,4 @@ deepseek-protocol = { path = "../protocol", version = "0.8.4" }
 deepseek-state = { path = "../state", version = "0.8.4" }
 deepseek-tools = { path = "../tools", version = "0.8.4" }
 serde_json.workspace = true
-tokio.workspace = true
 uuid.workspace = true

crates/mcp/Cargo.toml

@@ -8,6 +8,5 @@ description = "MCP server lifecycle and tool proxy compatibility for DeepSeek wo
 
 [dependencies]
 anyhow.workspace = true
-deepseek-protocol = { path = "../protocol", version = "0.8.4" }
 serde.workspace = true
 serde_json.workspace = true

crates/tui/Cargo.toml

@@ -14,19 +14,16 @@ path = "src/main.rs"
 [dependencies]
 anyhow = "1.0.100"
 arboard = "3.4"
-deepseek-tui-cli = { path = "../cli", version = "0.8.4" }
 deepseek-secrets = { path = "../secrets", version = "0.8.4" }
 deepseek-tools = { path = "../tools", version = "0.8.4" }
 async-stream = "0.3.6"
 async-trait = "0.1"
-bytes = "1.11.0"
 base64 = "0.22.1"
 axum = { version = "0.8.4", features = ["json"] }
 clap = { version = "4.5.54", features = ["derive"] }
 clap_complete = "4.5"
 colored = "3.0.0"
 crossterm = "0.28"
-csv = "1.4"
 dotenvy = "0.15.7"
 dirs = "6.0.0"
 futures-util = "0.3.31"
@@ -44,7 +41,6 @@ tokio-util = { version = "0.7.16", features = ["io"] }
 unicode-width = "0.2"
 unicode-segmentation = "1.12"
 uuid = { version = "1.11", features = ["v4"] }
-tokio-stream = "0.1"
 chrono = { version = "0.4", features = ["serde"] }
 tempfile = "3.16"
 thiserror = "2.0"