test(transform): cover hydrate trigger validation with Angular's cases - #502

Adds 8 tests to crates/oxc_angular_compiler/tests/r3_template_transform_test.rs, one for each hydrate validation case in Angular's packages/compiler/test/render3/r3_template_transform_spec.ts (lines 1698-1757 on angular/angular main) that had no coverage here. The conformance fixture lists these cases with empty assertions because they use toThrowError(...) / not.toThrow(), which the extractor does not handle (crates/angular_conformance/src/extractor/assertion_handlers.rs).

Each test uses the upstream template and expected message:

• parameter on a hydrate trigger with a reference-based equivalent: Hydration trigger "interaction" cannot have parameters
• no missing-reference error on hydrate on viewport
• never without hydrate (also with prefetch): Unrecognized trigger
• hydrate never followed by extra characters: Unrecognized trigger
• hydrate never with additional blocks, with spaces, and after another block: no Unrecognized trigger
• hydrate never before or after another hydrate trigger: Cannot specify additional `hydrate` triggers if `hydrate never` is present

Evidence:

• All 8 pass on current main, so no validator change was needed.
• cargo test -p oxc_angular_compiler: 2856 passed, 0 failed. cargo fmt --check is clean.
• To check that the tests can fail, I mutated transform/control_flow.rs locally. Making is_hydrate_never_pattern always return false fails the three "no error with hydrate never" tests and the combined-trigger test. Renaming the three error messages fails the four tests that expect an error. Together the two mutations fail 7 of the 8 tests; should_not_report_missing_reference_on_hydrate_trigger is not exercised by either.