chore(release): 1.2.0 (#30)

Bump 1.1.4 -> 1.2.0 across all release files (Cargo, pyproject, wasm,
conda, docs) and roll the CHANGELOG [Unreleased] section into [1.2.0].

Highlights: runtime CPU-feature dispatch (multiversion), broader wheel
coverage (linux aarch64 + musllinux + windows arm64), abi3 wheels,
Dynamic Time Warping, and indicator-specific exception types.

crates/ferro_ta_core/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ferro_ta_core"
-version = "1.1.4"
+version = "1.2.0"
 edition = "2021"
 description = "Pure Rust core indicator library — no PyO3, no numpy dependency"
 license = "MIT"

crates/ferro_ta_core/README.md

@@ -13,7 +13,7 @@ PyO3, NumPy, or Python runtime dependency, which makes it a good fit for:
 
 ```toml
 [dependencies]
-ferro_ta_core = "1.1.4"
+ferro_ta_core = "1.2.0"
 ```
 
 ## Design