Anchor a property backing field's location on its property declaration (the
`val`/`var` keyword to the end of the declaration) rather than the raw IR
offset. The raw `IrField` offset is inconsistent between frontends: under
`-language-version 1.9` it includes leading modifiers in the span start, while
under 2.0 it starts at the `val`/`var` keyword.
Example: `private val privateProp: Int = 0`
before (lang 1.9): properties.kt:35:5:35:32 | int privateProp; (col 5 = `private`)
after (lang 1.9): properties.kt:35:13:35:32 | int privateProp; (col 13 = `val`)
lang 2.0 (unchanged): properties.kt:35:13:35:32 | int privateProp;
The property entity already uses this PSI-based anchor (getPsiBasedLocation),
so the field now matches its own property location, which is what the 2.0
frontend already emits.
Delegated properties are excluded via `isDelegated`: their field is the
`$delegate` storage, whose location is the delegate expression rather than the
property declaration, and is converged separately.
This is a no-op for `-language-version 2.0` (only test-kotlin1 expected files
change); the two suites' backing-field and field-type-access locations now
agree.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>