RFR: 8285150: Improve tab completion for annotations [v5]

[Jan Lahoda]

> When using types code like:
> 
> @Deprecated(
> 
> 
> and presses `<tab>`, there should be a sensible completion, but currently there is nothing. This PR proposes to add code completion for annotation attributes.

Jan Lahoda has updated the pull request incrementally with one additional commit since the last revision:

  Adding Test annotation

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/22840/files
  - new: https://git.openjdk.org/jdk/pull/22840/files/35311d8e..d99640d3

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22840&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22840&range=03-04

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/22840.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22840/head:pull/22840

PR: https://git.openjdk.org/jdk/pull/22840