Simplify boilerplate for learning: stub inference and Postgres write

Removed ort/ndarray/image (ONNX Runtime inference) and sqlx (Postgres audit
write). inference::detect() and the Postgres half of reporter::report() are
now stubs with a comment for what real code goes there. Redis Streams
XREADGROUP loop and the Redis pub/sub alert stay real.

Verified with a clean cargo check --all-targets (0 warnings).

Cargo.toml

@@ -2,7 +2,7 @@
 name = "continuum-ai-worker"
 version = "0.1.0"
 edition = "2021"
-description = "Continuum AI worker — consumes camera frame batches from Redis Streams and runs ONNX Runtime print-failure detection"
+description = "Continuum AI worker — consumes camera frame batches from Redis Streams and runs print-failure detection"
 license = "UNLICENSED"
 
 [[bin]]
@@ -12,21 +12,13 @@ path = "src/main.rs"
 [dependencies]
 tokio = { version = "1.40", features = ["full"] }
 redis = { version = "0.27", features = ["tokio-comp", "streams"] }
-ort = { version = "2.0.0-rc.9", features = ["ndarray", "download-binaries"] }
-ndarray = "0.17"
-image = "0.25"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter", "json"] }
 anyhow = "1"
-thiserror = "1"
-base64 = "0.22"
-sqlx = { version = "0.8", features = ["runtime-tokio", "postgres", "chrono", "uuid"] }
-uuid = { version = "1", features = ["v4", "serde"] }
-chrono = { version = "0.4", features = ["serde"] }
 dotenvy = "0.15"
 
-[profile.release]
-opt-level = 3
-lto = true
+# Real inference (ONNX Runtime via the `ort` crate) and the Postgres audit
+# write (via `sqlx`) go here once src/inference and src/reporter grow past
+# their stubs — see those modules' doc comments.