feat(rvcsi): rvcsi-core + napi-c Nexmon shim + crate skeletons (ADR-095/096)

First implementation milestone for the rvCSI edge RF sensing runtime:

- rvcsi-core — the foundation: CsiFrame/CsiWindow/CsiEvent normalized schema,
  ValidationStatus, AdapterProfile, CsiSource plugin trait, id newtypes +
  IdGenerator, RvcsiError, and the validate_frame pipeline (length/finiteness/
  subcarrier/RSSI/monotonicity hard checks + multiplicative quality scoring →
  Accepted/Degraded/Recovered/Rejected). 29 unit tests, forbid(unsafe_code).
- rvcsi-adapter-nexmon — the napi-c boundary: native/rvcsi_nexmon_shim.{c,h}
  (the only C in the runtime, allocation-free, bounds-checked, parses/writes a
  byte-defined "rvCSI Nexmon record" — a normalized superset of the nexmon_csi
  UDP payload), compiled via build.rs + cc, wrapped by a documented ffi module
  and a NexmonAdapter implementing CsiSource. 9 tests round-tripping through C.
- Workspace registration in v2/Cargo.toml (8 new members + napi/cc workspace
  deps) and compiling skeletons for rvcsi-dsp, rvcsi-events, rvcsi-adapter-file,
  rvcsi-ruvector, rvcsi-node (napi-rs cdylib + build.rs napi_build::setup) and
  rvcsi-cli (`rvcsi` binary) — to be filled in by the implementation swarm.

cargo build -p rvcsi-core -p rvcsi-adapter-nexmon -p rvcsi-node -p rvcsi-cli: OK
cargo test  -p rvcsi-core -p rvcsi-adapter-nexmon: 38 passed, 0 failed

https://claude.ai/code/session_01CdYAPvRTjcch6YrYf42n1z

v2/crates/rvcsi-cli/src/main.rs

@@ -0,0 +1,33 @@
+//! `rvcsi` — the rvCSI command-line tool (skeleton; completed during integration).
+//!
+//! Subcommands (ADR-095 FR7): `inspect`, `replay`, `stream`, `calibrate`,
+//! `health`, `export`. The skeleton wires `inspect` so the binary is usable;
+//! the rest are filled in by the CLI swarm agent / integration step.
+
+use clap::{Parser, Subcommand};
+
+#[derive(Parser)]
+#[command(name = "rvcsi", version, about = "rvCSI — edge RF sensing runtime CLI")]
+struct Cli {
+    #[command(subcommand)]
+    command: Command,
+}
+
+#[derive(Subcommand)]
+enum Command {
+    /// Print a summary of a capture file (frame count, channels, quality).
+    Inspect {
+        /// Path to a `.rvcsi` capture file.
+        path: String,
+    },
+}
+
+fn main() -> anyhow::Result<()> {
+    let cli = Cli::parse();
+    match cli.command {
+        Command::Inspect { path } => {
+            println!("rvcsi inspect: {path} (not yet implemented in the skeleton)");
+            Ok(())
+        }
+    }
+}