feat(xtask): consolidate CI workflows onto xtask helpers (#542)

- split the xtask crate into structured modules for
  - bindings
  - ci
  - dev
  - util
  - no-std
- Adding commands for
  - ci-release/ci-debug
  - MUSL/no-std
  - per- binding language smoke tests
  - developer tasks (fmt, clippy, pre-commit, pre-push)
- refresh Cargo manifests/locks, binding readmes, and shared FFI helpers so every binding reuses the same preparation steps
- refactor GitHub Actions (release/debug, extensions, CodeQL, clippy, bindings) to call the new xtask commands
- Use rust-cache in ci workflows (microsoft qdk also does this)
- extend README with a contributor workflow section describing how xtask mirrors CI expectations
- update pre-commit and pre-push hooks to use the xtask dev commands

WORKAROUND:
When dotnet is run from an xtask, codeql tracer intercepts it an routes to a nonexistent binary.
Therefore in codeql workflow, xtask is not used for c# and instead dotnet is directly invoked.
Tracked by #545

closes #475

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

.github/workflows/pr-extensions.yml

@@ -21,18 +21,15 @@ jobs:
     - uses: actions/checkout@08eba0b27e820071cde6df949e0beb9ba4906955 # v4
     - name: Setup Rust toolchain
       uses: ./.github/actions/toolchains/rust
-    - name: Build only std
-      run: cargo build -r --example regorus --no-default-features --features "std,rego-extensions"
-    - name: Doc Tests
-      run: cargo test -r --doc --features rego-extensions
-    - name: Run tests
-      run: cargo test -r --features rego-extensions
-    - name: Run example
-      run: cargo run --example regorus --features rego-extensions -- eval -d examples/server/allowed_server.rego -i examples/server/input.json data.example
-    - name: Run tests (ACI)
-      run: cargo test -r --test aci --features rego-extensions
-    - name: Run tests (KATA)
-      run: cargo test -r --test kata --features rego-extensions
-    - name: Run tests (OPA Conformance)
+    - name: Cache cargo
+      uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
+      with:
+        shared-key: ${{ runner.os }}-regorus
+    - name: Fetch dependencies
+      run: cargo fetch --locked
+    - name: Run rego extensions CI suite
       run: >-
-        cargo test -r --test opa --features opa-testutil,serde_json/arbitrary_precision,rego-extensions  -- $(tr '\n' ' ' < tests/opa.passing)
+        cargo xtask ci-release --frozen --features rego-extensions
+        --skip-all-features-build --skip-no-default-features-tests
+        --skip-azure-policy --skip-azure-rbac
+        --opa-features "opa-testutil,serde_json/arbitrary_precision,rego-extensions"