multiple feature and performance improvements (see description)

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Release notes — 2025-08-12

Highlights

Agent back to near-zero CPU when idle (request-driven, no background samplers).
Accurate per-process CPU% via /proc deltas; only top-level processes (threads hidden).
TUI: processes pane gets scrollbar, click-to-sort (CPU% or Mem) with indicator, stable total count.
Network panes made taller; disks slightly reduced.
README revamped: rustup prereqs, crates.io install, update/systemd instructions.
Clippy cleanups across agent and client.
Agent

Reverted precompressed caches and background samplers; WebSocket path is request-driven again.
Ensured on-demand gzip for larger replies; no per-request overhead when small.
Processes: switched to refresh_processes_specifics with ProcessRefreshKind::everything().without_tasks() to exclude threads.
Per-process CPU% now computed from /proc jiffies deltas using a small ProcCpuTracker (fixes “always 0%”/scaling issues).
Optional metrics and light caching:
CPU temp and GPU metrics gated by env (SOCKTOP_AGENT_TEMP=0, SOCKTOP_AGENT_GPU=0).
Tiny TTL caches via once_cell to avoid rescanning sensors every tick.
Dependencies: added once_cell = "1.19".
No API changes to WS endpoints.
Client (TUI)

Processes pane:
Scrollbar (mouse wheel, drag; keyboard arrows/PageUp/PageDown/Home/End).
Click header to sort by CPU% or Mem; dot indicator on active column.
Preserves process_count across fast metrics updates to avoid flicker.
UI/theme:
Shared scrollbar colors moved to ui/theme.rs; both CPU and Processes reuse them.
Cached pane rect to fix input handling; removed unused vars.
Layout: network download/upload get more vertical space; disks shrink slightly.
Clippy fixes: derive Default for ProcSortBy; style/import cleanups.
Docs

README: added rustup install steps (with proper shell reload), install via cargo install socktop and cargo install socktop_agent, and a clear Updating section (systemd service steps included).
Features list updated; roadmap marks independent cadences as done.
Upgrade notes

Agent: cargo install socktop_agent --force, then restart your systemd service; if unit changed, systemctl daemon-reload.
TUI: cargo install socktop --force.
Optional envs to trim overhead: SOCKTOP_AGENT_GPU=0, SOCKTOP_AGENT_TEMP=0.
No config or API breaking changes.

Cargo.lock

@@ -278,6 +278,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "crc32fast"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9481c1c90cbf2ac953f07c8d4a58aa3945c425b7185c9154d67a65e4230da511"
+dependencies = [
+ "cfg-if",
+]
+
 [[package]]
 name = "crossterm"
 version = "0.27.0"
@@ -413,6 +422,16 @@ dependencies = [
  "windows-sys 0.60.2",
 ]
 
+[[package]]
+name = "flate2"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4a3d7db9596fecd151c5f638c0ee5d5bd487b6e0ea232e5dc96d5250f6f94b1d"
+dependencies = [
+ "crc32fast",
+ "miniz_oxide",
+]
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -541,7 +560,19 @@ checksum = "335ff9f135e4384c8150d6f27c6daed433577f86b4750418338c01a1a2528592"
 dependencies = [
  "cfg-if",
  "libc",
- "wasi",
+ "wasi 0.11.1+wasi-snapshot-preview1",
+]
+
+[[package]]
+name = "getrandom"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26145e563e54f2cadc477553f1ec5ee650b00862f0a58bcd12cbdc5f0ea2d2f4"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "r-efi",
+ "wasi 0.14.2+wasi-0.2.4",
 ]
 
 [[package]]
@@ -986,7 +1017,7 @@ checksum = "a4a650543ca06a924e8b371db273b2756685faae30f8487da1b56505a8f78b0c"
 dependencies = [
  "libc",
  "log",
- "wasi",
+ "wasi 0.11.1+wasi-snapshot-preview1",
  "windows-sys 0.48.0",
 ]
 
@@ -998,7 +1029,7 @@ checksum = "78bed444cc8a2160f01cbcf811ef18cac863ad68ae8ca62092e8db51d51c761c"
 dependencies = [
  "libc",
  "log",
- "wasi",
+ "wasi 0.11.1+wasi-snapshot-preview1",
  "windows-sys 0.59.0",
 ]
 
@@ -1176,6 +1207,12 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "r-efi"
+version = "5.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
+
 [[package]]
 name = "rand"
 version = "0.8.5"
@@ -1183,8 +1220,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
 dependencies = [
  "libc",
- "rand_chacha",
- "rand_core",
+ "rand_chacha 0.3.1",
+ "rand_core 0.6.4",
+]
+
+[[package]]
+name = "rand"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6db2770f06117d490610c7488547d543617b21bfa07796d7a12f6f1bd53850d1"
+dependencies = [
+ "rand_chacha 0.9.0",
+ "rand_core 0.9.3",
 ]
 
 [[package]]
@@ -1194,7 +1241,17 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
 dependencies = [
  "ppv-lite86",
- "rand_core",
+ "rand_core 0.6.4",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3022b5f1df60f26e1ffddd6c66e8aa15de382ae63b3a0c1bfc0e4d3e3f325cb"
+dependencies = [
+ "ppv-lite86",
+ "rand_core 0.9.3",
 ]
 
 [[package]]
@@ -1203,7 +1260,16 @@ version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.16",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "99d9a13982dcf210057a8a78572b2217b667c3beacbf3a0d8b454f6f82837d38"
+dependencies = [
+ "getrandom 0.3.3",
 ]
 
 [[package]]
@@ -1457,6 +1523,7 @@ dependencies = [
  "anyhow",
  "chrono",
  "crossterm 0.27.0",
+ "flate2",
  "futures",
  "futures-util",
  "ratatui",
@@ -1464,7 +1531,7 @@ dependencies = [
  "serde_json",
  "tokio",
  "tokio-tungstenite",
- "tungstenite",
+ "tungstenite 0.27.0",
  "url",
 ]
 
@@ -1473,16 +1540,19 @@ name = "socktop_agent"
 version = "0.1.0"
 dependencies = [
  "axum",
+ "flate2",
  "futures",
  "futures-util",
  "gfxinfo",
  "nvml-wrapper",
+ "once_cell",
  "serde",
  "serde_json",
  "sysinfo",
  "tokio",
  "tracing",
  "tracing-subscriber",
+ "tungstenite 0.27.0",
 ]
 
 [[package]]
@@ -1666,7 +1736,7 @@ dependencies = [
  "futures-util",
  "log",
  "tokio",
- "tungstenite",
+ "tungstenite 0.24.0",
 ]
 
 [[package]]
@@ -1771,12 +1841,29 @@ dependencies = [
  "http",
  "httparse",
  "log",
- "rand",
+ "rand 0.8.5",
  "sha1",
  "thiserror 1.0.69",
  "utf-8",
 ]
 
+[[package]]
+name = "tungstenite"
+version = "0.27.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eadc29d668c91fcc564941132e17b28a7ceb2f3ebf0b9dae3e03fd7a6748eb0d"
+dependencies = [
+ "bytes",
+ "data-encoding",
+ "http",
+ "httparse",
+ "log",
+ "rand 0.9.2",
+ "sha1",
+ "thiserror 2.0.12",
+ "utf-8",
+]
+
 [[package]]
 name = "typenum"
 version = "1.18.0"
@@ -1853,6 +1940,15 @@ version = "0.11.1+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ccf3ec651a847eb01de73ccad15eb7d99f80485de043efb2f370cd654f4ea44b"
 
+[[package]]
+name = "wasi"
+version = "0.14.2+wasi-0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9683f9a5a998d873c0d21fcbe3c083009670149a8fab228644b8bd36b2c48cb3"
+dependencies = [
+ "wit-bindgen-rt",
+]
+
 [[package]]
 name = "wasm-bindgen"
 version = "0.2.100"
@@ -2332,6 +2428,15 @@ version = "0.53.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "271414315aff87387382ec3d271b52d7ae78726f5d44ac98b4f4030c91880486"
 
+[[package]]
+name = "wit-bindgen-rt"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6f42320e61fe2cfd34354ecb597f86f413484a798ba44a8ca1165c58d42da6c1"
+dependencies = [
+ "bitflags",
+]
+
 [[package]]
 name = "wmi"
 version = "0.15.2"