Add support for sync to AWS

This approach is very similar to that of GCP, and utilizes a similar
conditional-write mechanism to prevent conflicting updates to the
`latest` key.

This updates the package major version to 1.0.0, as it modifies the
`ServerConfig` enum by adding a new variant -- a semver-breaking change.
To avoid further major version bumps from additional variants, this also
adds `#[non-exhaustive]` to the enum.

.github/workflows/checks.yml

@@ -29,7 +29,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: "1.73.0" # MSRV
+          toolchain: "1.78.0" # MSRV
           override: true
           components: clippy
 

.github/workflows/rust-tests.yml

@@ -16,6 +16,8 @@ jobs:
         features:
           - ""
           - "server-sync"
+          - "server-gcp"
+          - "server-aws"
           - "tls-native-roots"
 
     name: "taskchampion ${{ matrix.features == '' && 'with no features' || format('with features {0}', matrix.features) }}"
@@ -53,7 +55,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - "1.73.0" # MSRV
+          - "1.78.0" # MSRV
           - "stable"
         os:
           - ubuntu-latest