Fix nested type property decorator completions

[jeskew]

Resolves #11970

The LS is currently looking at the type of the top-level statement in which a cursor is located when proposing decorator completions. This means that for a scenario like the following:

type obj = {
  @|
  prop: int
}

the LS will propose completions for decorators that can be used on objects (the type of the full type obj = {...} statement) rather than decorators that can be used on integers (the type of the decorator's target). Consequently, the LS is proposing completions that will raise an error diagnostic (like @sealed() or @discriminator()) and not proposing completions that would be valid (like @minValue()).

Microsoft Reviewers: Open in CodeFlow

[github-actions]

Test this change out locally with the following install scripts (Action run 6341807474)

VSCode

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-vsix.sh) --run-id 6341807474

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-vsix.ps1) } -RunId 6341807474"

Azure CLI

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-cli.sh) --run-id 6341807474

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-cli.ps1) } -RunId 6341807474"

[github-actions]

Test Results

     132 files   -      11       132 suites   - 11   3h 15m 43s ⏱️ - 25m 22s
10 658 tests +       1  10 658 ✔️ +       1  0 💤 ±0  0 ❌ ±0 
51 499 runs   - 2 834  51 499 ✔️  - 2 834  0 💤 ±0  0 ❌ ±0 

Results for commit 8961bad. ± Comparison against base commit 6f58518.

[majastrz]