refactor: remove duplicated format and orbital-mechanics implementations

.github/workflows/ci.yml

@@ -96,19 +96,6 @@ jobs:
       - run: bash scripts/check_no_todos.sh
       - run: bash scripts/check_legacy_name_refs.sh
 
-  feature-checks:
-    name: Targeted feature checks
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        feature: [lisa, doris, parquet, de440]
-    steps:
-      - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@stable
-      - uses: Swatinem/rust-cache@v2
-      - run: cargo check --workspace --no-default-features --features ${{ matrix.feature }}
-
   msrv:
     name: MSRV (Rust 1.89)
     runs-on: ubuntu-latest

CHANGELOG.md

@@ -8,6 +8,12 @@ follows [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### Changed
 
+- Removed duplicated generic format, TLE, and SPICE implementations in favor
+  of canonical Siderust APIs. Lambert is intentionally outside the core
+  service product scope.
+- Retained the full Vallado-style SGP4/SDP4 implementation temporarily because
+  Siderust does not yet provide semantic parity; migration is tracked by
+  spod #29 and Siderust #98.
 - Renamed the project and Cargo package to `spod`, including the `spod` and
   `spod-rest` binaries, repository metadata, Docker examples, and REST
   configuration variables.