pst api adjustments, additional doc

[victornicolet]

Description of changes

This makes a few adjustments in the PST API:

• try_into_pst now suceeds even if there is no lossless representation. This allows using try_into_pst for policies that are residuals from TPE (prior implementation would return an error). Eliminates an error type.
• adds documentation and examples.
• adds PartialEq and Eq to the PST types that were missing it,
• re-exports some types from dependencies in the pst module, so that crates depending on Cedar don't have to add dependencies, or manage dependency version to match Cedar's.

The last change is probably the one most worth discussing, but I think it makes the API cleaner.

Checklist for requesting a review

The change in this PR is (choose one, and delete the other options):

• A change (breaking or otherwise) that only impacts unreleased or experimental code.

I confirm that this PR (choose one, and delete the other options):

• Updates the "Unreleased" section of the CHANGELOG with a description of my change (required for major/minor version bumps).

I confirm that cedar-spec (choose one, and delete the other options):

• Does not require updates because my change does not impact the Cedar formal model or DRT infrastructure.

I confirm that docs.cedarpolicy.com (choose one, and delete the other options):

• Does not require updates because my change does not impact the Cedar language specification.

[github-actions]

Coverage Report

Head Commit: f0f19dd1102a24a3187793d4e283d5089bbac864

Base Commit: 18cfa43f342371e0f694249c020b353728b56100

Download the full coverage report.

Coverage of Added or Modified Lines of Rust Code

Required coverage: 80.00%

Actual coverage: 100.00%

Status: PASSED ✅

Details

File	Status	Covered	Coverage	Missed Lines
cedar-policy/src/api.rs	🟢	14/14	100.00%

Coverage of All Lines of Rust Code

Required coverage: 80.00%

Actual coverage: 87.67%

Status: PASSED ✅

Details

Package	Status	Covered	Coverage	Base Coverage
cedar-language-server	🟢	4722/5102	92.55%	--
cedar-policy	🟡	4255/5363	79.34%	--
cedar-policy-cli	🟡	1210/1614	74.97%	--
cedar-policy-core	🟢	23907/27178	87.96%	--
cedar-policy-formatter	🟢	914/1088	84.01%	--
cedar-policy-symcc	🟢	6752/7262	92.98%	--
cedar-wasm	🔴	0/28	0.00%	--

[github-actions]

Coverage Report

Head Commit: 52af9a55c9b8900f51ac4166511eb56a3e0061a7

Base Commit: 18cfa43f342371e0f694249c020b353728b56100

Download the full coverage report.

Coverage of Added or Modified Lines of Rust Code

Required coverage: 80.00%

Actual coverage: 100.00%

Status: PASSED ✅

Details

File	Status	Covered	Coverage	Missed Lines
cedar-policy/src/api.rs	🟢	14/14	100.00%

Coverage of All Lines of Rust Code

Required coverage: 80.00%

Actual coverage: 87.67%

Status: PASSED ✅

Details

Package	Status	Covered	Coverage	Base Coverage
cedar-language-server	🟢	4722/5102	92.55%	--
cedar-policy	🟡	4255/5363	79.34%	--
cedar-policy-cli	🟡	1210/1614	74.97%	--
cedar-policy-core	🟢	23907/27178	87.96%	--
cedar-policy-formatter	🟢	914/1088	84.01%	--
cedar-policy-symcc	🟢	6752/7262	92.98%	--
cedar-wasm	🔴	0/28	0.00%	--

[john-h-kastner-aws]

I didn't make any changes to the existing TPE code, so you can just overwrite tpe.rs with your updated version of the module

[github-actions]

Coverage Report

Head Commit: 7bc7281d86956b8741309615d3e627ea2fc372c4

Base Commit: 63b79962b5f3b42d67b02df01e66b860b20fe539

Download the full coverage report.

Coverage of Added or Modified Lines of Rust Code

Required coverage: 80.00%

Actual coverage: 100.00%

Status: PASSED ✅

Details

File	Status	Covered	Coverage	Missed Lines
cedar-policy/src/api.rs	🟢	14/14	100.00%

Coverage of All Lines of Rust Code

Required coverage: 80.00%

Actual coverage: 87.66%

Status: PASSED ✅

Details

Package	Status	Covered	Coverage	Base Coverage
cedar-language-server	🟢	4722/5102	92.55%	--
cedar-policy	🟡	4244/5352	79.30%	--
cedar-policy-cli	🟡	1210/1614	74.97%	--
cedar-policy-core	🟢	23907/27178	87.96%	--
cedar-policy-formatter	🟢	914/1088	84.01%	--
cedar-policy-symcc	🟢	6752/7262	92.98%	--
cedar-wasm	🔴	0/28	0.00%	--