test(azure_policy): add foundation test cases

[anakrish]

YAML-driven test cases for the core Azure Policy compiler. These cover alias resolution, field conditions, logical operators, type coercion, count expressions, template functions, effect compilation, and policy definition parsing.

24 files, each a self-contained scenario exercised by the test runner in the companion code PR.

Part 1 of 3 — split from #695 to enable Copilot review on each PR individually.

[Copilot]

Pull request overview

Adds a set of YAML scenario files under tests/azure_policy/cases/ to serve as “foundation” test vectors for the Azure Policy compiler/evaluator (to be exercised by the companion test-runner PR). The cases cover conditions/operators, expression/template-function evaluation, count semantics, effects/details, policy-definition envelope parsing, and various edge/corner cases (casing, coercion, deep nesting, parse errors).

Changes:

• Add YAML test suites for core condition/evaluation semantics (operators, logical combinators, value LHS, exists, implicit allOf on [*], type coercion).
• Add YAML test suites for ARM template-expression/function support (core functions + extra string/collection/numeric + datetime/IP).
• Add YAML test suites for policy-rule/effect compilation (effects, effect details, modify alias-modifiability checks, policy definition envelope parsing, parse error scenarios, complex policies).

Reviewed changes

Copilot reviewed 24 out of 24 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/azure_policy/cases/value_conditions.yaml	Scenarios for value-LHS conditions (literals, expressions, arrays, combinators).
tests/azure_policy/cases/type_coercion.yaml	Scenarios for string↔number/bool coercion, null/undefined, and Unicode comparisons.
tests/azure_policy/cases/template_functions_extra.yaml	Additional ARM template function coverage (string/collection/numeric).
tests/azure_policy/cases/template_functions_datetime_ip.yaml	Datetime functions (utcNow, epoch conversion, addDays) + ipRangeContains.
tests/azure_policy/cases/template_functions.yaml	Baseline ARM template function coverage (split, empty, first/last, int/string/bool, etc.).
tests/azure_policy/cases/policy_definition.yaml	Scenarios for parsing/evaluating full policy definition envelopes (wrapped/unwrapped).
tests/azure_policy/cases/parse_errors.yaml	Negative parsing scenarios for malformed policy JSON / invalid constructs.
tests/azure_policy/cases/operators.yaml	Coverage for Azure Policy condition operators with field-based conditions.
tests/azure_policy/cases/modifiable_check.yaml	Modify-effect alias “Modifiable” validation scenarios (using an aliases file).
tests/azure_policy/cases/logical_combinators.yaml	Scenarios for allOf/anyOf/not and nested combinations.
tests/azure_policy/cases/implicit_allof.yaml	Scenarios for implicit “all elements must match” semantics for field[*] outside count.
tests/azure_policy/cases/fields.yaml	Scenarios for built-in fields + tag access syntaxes and nested field paths.
tests/azure_policy/cases/field_wildcard_collect.yaml	Scenarios for field('path[*]') collection returning arrays (including missing-array handling).
tests/azure_policy/cases/expressions.yaml	Scenarios for ARM template expressions across field/value/effect positions and contexts.
tests/azure_policy/cases/exists.yaml	Comprehensive exists operator scenarios (nulls, missing, objects/arrays, deep paths).
tests/azure_policy/cases/effects.yaml	Scenarios for effect kinds (simple and cross-resource), parameterized effects, casing.
tests/azure_policy/cases/effect_details.yaml	Scenarios validating structured effect-result details shapes and expression evaluation within details.
tests/azure_policy/cases/deep_nesting.yaml	Stress/edge scenarios for deep nesting, nested expressions, nested counts, missing-field operator behavior.
tests/azure_policy/cases/complex_policies.yaml	Higher-level realistic policy scenarios combining multiple features end-to-end.
tests/azure_policy/cases/casing.yaml	Extensive case-insensitivity and casing semantics scenarios (ARM key casing vs policy value folding).

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Pull request overview

Copilot reviewed 24 out of 24 changed files in this pull request and generated 1 comment.

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Pull request overview

Copilot reviewed 24 out of 24 changed files in this pull request and generated no new comments.

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