feat: ADR-024 Contrastive CSI Embedding Model — all 7 phases (#52)

Full implementation of Project AETHER — Contrastive CSI Embedding Model.

## Phases Delivered
1. ProjectionHead (64→128→128) + L2 normalization
2. CsiAugmenter (5 physically-motivated augmentations)
3. InfoNCE contrastive loss + SimCLR pretraining
4. FingerprintIndex (4 index types: env, activity, temporal, person)
5. RVF SEG_EMBED (0x0C) + CLI integration
6. Cross-modal alignment (PoseEncoder + InfoNCE)
7. Deep RuVector: MicroLoRA, EWC++, drift detection, hard-negative mining, SEG_LORA

## Stats
- 276 tests passing (191 lib + 51 bin + 16 rvf + 18 vitals)
- 3,342 additions across 8 files
- Zero unsafe/unwrap/panic/todo stubs
- ~55KB INT8 model for ESP32 edge deployment

Also fixes deprecated GitHub Actions (v3→v4) and adds feat/* branch CI triggers.

Closes #50

rust-port/wifi-densepose-rs/crates/wifi-densepose-signal/Cargo.toml

@@ -4,6 +4,12 @@ version.workspace = true
 edition.workspace = true
 description = "WiFi CSI signal processing for DensePose estimation"
 license.workspace = true
+authors = ["rUv <ruv@ruv.net>", "WiFi-DensePose Contributors"]
+repository.workspace = true
+documentation = "https://docs.rs/wifi-densepose-signal"
+keywords = ["wifi", "csi", "signal-processing", "densepose", "rust"]
+categories = ["science", "computer-vision"]
+readme = "README.md"
 
 [dependencies]
 # Core utilities
@@ -27,7 +33,7 @@ ruvector-attention = { workspace = true }
 ruvector-solver = { workspace = true }
 
 # Internal
-wifi-densepose-core = { path = "../wifi-densepose-core" }
+wifi-densepose-core = { version = "0.1.0", path = "../wifi-densepose-core" }
 
 [dev-dependencies]
 criterion = { version = "0.5", features = ["html_reports"] }