ui: Tooltip descriptions for gpu SASS and stall frames

[manojVivek]

Screenshots:

[alwaysmeticulous]

🔴 Meticulous spotted visual differences in 5 of 288 screens tested: view and approve differences detected.

Meticulous evaluated ~4 hours of user flows against your PR.

_{Last updated for commit 32b313f [pre-commit.ci lite] apply automatic fixes. This comment will update as new commits are pushed.}