feat: expanded add_card_button_srv docs

[kpagacz]

Related to insightsengineering/teal#632

[github-actions]

Code Coverage Summary

Filename              Stmts    Miss  Cover    Missing
------------------  -------  ------  -------  ---------------------------------------------
R/AddCardModule.R        82       3  96.34%   71-73
R/ContentBlock.R         16       0  100.00%
R/DownloadModule.R      137      24  82.48%   74-76, 97, 154-158, 161-165, 172-176, 179-183
R/NewpageBlock.R          2       0  100.00%
R/PictureBlock.R         31       0  100.00%
R/Previewer.R           215      11  94.88%   156, 158-161, 166-172
R/Renderer.R             54       4  92.59%   142, 144-145, 166
R/ReportCard.R           47       0  100.00%
R/Reporter.R             43       0  100.00%
R/ResetModule.R          45       0  100.00%
R/SimpleReporter.R       18       0  100.00%
R/TableBlock.R            9       0  100.00%
R/TealReportCard.R        9       0  100.00%
R/TextBlock.R             7       0  100.00%
R/yaml_utils.R           74       2  97.30%   65, 260
TOTAL                   789      44  94.42%

Results for commit: 0a5b2e9

Minimum allowed coverage is 80%

♻️ This comment has been updated with latest results

[github-actions]

Unit Tests Summary

    1 files    15 suites   8s ⏱️
137 tests 137 ✔️ 0 💤 0 ❌
186 runs  186 ✔️ 0 💤 0 ❌

Results for commit ec2b4f5.

♻️ This comment has been updated with latest results.

[nikolas-burkoff]

Yup this feels like the right place for it