Remove Legacy FFI from LibChat (#80)

* Remove libchat legacy FFI

* Remove legacy nim bindings

* Remove stray headerfile

* Remove deprecated CI jobs

.github/workflows/ci.yml

@@ -36,23 +36,3 @@ jobs:
       - run: rustup update stable && rustup default stable
       - run: rustup component add rustfmt
       - run: cargo fmt --all -- --check
-
-  nim-bindings-test:
-    name: Nim Bindings Test
-    runs-on: ${{ matrix.os }}
-    strategy:
-      matrix:
-        os: [ubuntu-latest, macos-latest]
-    steps:
-      - uses: actions/checkout@v4
-      - run: rustup update stable && rustup default stable
-      - name: Install Nim via choosenim
-        run: |
-          curl https://nim-lang.org/choosenim/init.sh -sSf | sh -s -- -y
-          echo "$HOME/.nimble/bin" >> $GITHUB_PATH
-      - run: nimble install -dy
-        working-directory: nim-bindings
-      - run: nimble test
-        working-directory: nim-bindings
-      - run: nimble pingpong
-        working-directory: nim-bindings