[AZ-640] Bootstrap Rust workspace, CI/Docker, observability scaffold

Lands the first task of the implementation epic AZ-626: a cargo workspace
with 14 crates (shared + autopilot binary + 12 component crates), a
multi-stage Dockerfile + dev/test compose stacks, a Woodpecker CI pipeline,
the on-airframe systemd unit with flight-gate wiring, three environment
TOML configs, and the canonical entity catalogue from data_model.md as
`shared::models`.

Per-AC verification (full detail in
_docs/03_implementation/batch_01_cycle1_report.md):

- AC-1 cargo check --workspace clean
- AC-2 cargo test --workspace passes; per-crate it_compiles() <0.01 s
- AC-6 cargo build/test --no-default-features clean; VlmClient default
       impl returns VlmAssessment::disabled()
- AC-9 tracing-subscriber emits JSON logs with ts/level/target/fields
- AC-10 runtime::ensure_state_directories creates mapobjects/, audit/,
        pending_pushes/ under storage.state_dir

Deferred to external infra (artifacts written, verification re-runs in CI
and in downstream tasks):
- AC-3 Woodpecker runner; CI yml in place
- AC-4 docker-compose mocks land with AZ-660/AZ-644/AZ-675
- AC-5 SITL conformance lands with AZ-641/AZ-648/AZ-652
- AC-7 aarch64 cross-compile via cargo-zigbuild stage
- AC-8 systemd unit (Linux + systemd host)

Layering invariants from module-layout.md hold: shared (L1) imports
nothing; Layer 2 actor crates import only shared; Layer 3 coordinators
(operator_bridge, mission_executor) import only their documented Layer 2
deps; Layer 4 (scan_controller) imports its documented Layer 2 + Layer 3
deps; the autopilot binary (L5) is the only consumer of every component.

cargo fmt --all --check + cargo clippy --all-targets -- -D warnings both
clean. Jira AZ-640 transitioned to In Progress at the start of this batch;
the matching In Testing transition follows this commit.

Co-authored-by: Cursor <cursoragent@cursor.com>

crates/telemetry_stream/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "telemetry_stream"
+version = "0.1.0"
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+publish.workspace = true
+authors.workspace = true
+
+[dependencies]
+shared = { workspace = true }
+tokio = { workspace = true }
+tracing = { workspace = true }
+async-trait = { workspace = true }

crates/telemetry_stream/src/lib.rs

@@ -0,0 +1,91 @@
+//! `telemetry_stream` — always-on uplink to the Ground Station + operator-command downlink.
+//!
+//! Real implementation lands in:
+//! - AZ-675 `telemetry_stream_grpc_server`
+//! - AZ-676 `telemetry_stream_video_path`
+//! - AZ-677 `telemetry_stream_mapobjects_snapshot`
+
+use async_trait::async_trait;
+use tokio::sync::mpsc;
+
+use shared::contracts::TelemetrySink;
+use shared::error::{AutopilotError, Result};
+use shared::health::ComponentHealth;
+use shared::models::detection::DetectionBatch;
+use shared::models::frame::Frame;
+use shared::models::operator::OperatorCommand;
+
+const NAME: &str = "telemetry_stream";
+
+pub struct TelemetryStream {
+    commands_tx: mpsc::Sender<OperatorCommand>,
+    commands_rx: Option<mpsc::Receiver<OperatorCommand>>,
+}
+
+impl TelemetryStream {
+    pub fn new(downlink_capacity: usize) -> Self {
+        let (commands_tx, commands_rx) = mpsc::channel(downlink_capacity);
+        Self {
+            commands_tx,
+            commands_rx: Some(commands_rx),
+        }
+    }
+
+    pub fn handle(&self) -> TelemetryStreamHandle {
+        TelemetryStreamHandle {
+            commands_tx: self.commands_tx.clone(),
+        }
+    }
+
+    /// Take the downlink command receiver. The composition root forwards it to
+    /// `operator_bridge` as `Receiver<OperatorCommand>`.
+    pub fn take_command_receiver(&mut self) -> Option<mpsc::Receiver<OperatorCommand>> {
+        self.commands_rx.take()
+    }
+}
+
+#[derive(Clone)]
+pub struct TelemetryStreamHandle {
+    commands_tx: mpsc::Sender<OperatorCommand>,
+}
+
+impl TelemetryStreamHandle {
+    /// Inject an operator command. Production path is fed by the downlink
+    /// receiver in `internal::downlink/*`; tests can call this directly.
+    pub async fn submit_command(&self, command: OperatorCommand) -> Result<()> {
+        self.commands_tx
+            .send(command)
+            .await
+            .map_err(|_| AutopilotError::Internal("downlink channel closed".into()))
+    }
+
+    pub fn health(&self) -> ComponentHealth {
+        ComponentHealth::disabled(NAME)
+    }
+}
+
+#[async_trait]
+impl TelemetrySink for TelemetryStreamHandle {
+    async fn push_frame(&self, _frame: Frame) -> Result<()> {
+        Err(AutopilotError::NotImplemented(
+            "telemetry_stream::push_frame (AZ-676)",
+        ))
+    }
+
+    async fn push_detections(&self, _batch: DetectionBatch) -> Result<()> {
+        Err(AutopilotError::NotImplemented(
+            "telemetry_stream::push_detections (AZ-675)",
+        ))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_compiles() {
+        let h = TelemetryStream::new(8).handle();
+        assert_eq!(h.health().level, shared::health::HealthLevel::Disabled);
+    }
+}