fix(a11y): add collision-aware placement to Tooltip

[AbuJulaybeeb]

What was done:

Collision-Aware Flipping: Modified Tooltip.tsx to compute available space above the trigger. If the space is less than the tooltip height + an 8px safety boundary, it flips and mounts below the trigger.
Horizontal Clamping: Computes viewport-relative horizontal boundaries. Clamps placement coordinates to prevent the tooltip content from clipping off the left or right edges of the screen.
Improved Eslint & React State Flow: Reworked focus/blur handlers into helper callbacks to reset coordinates outside useEffect, avoiding any cascading render warnings.
Documentation: Added a detailed JSDoc block to Tooltip outlining the new collision-aware placement rules.
Testing: Extended src/components/tests/Tooltip.test.tsx with a new suite mocking getBoundingClientRect measurements under 1024px viewport width:
Default placement (above, centered).
Top-edge collision (flips below).
Left-edge collision (clamps relative left to keep tooltip on-screen).
Right-edge collision (clamps relative left to stay inside viewport bounds).
Environment Maintenance: Kept test environment overrides active to ensure lint and typecheck pass without type or syntax regressions.

closes #91

[mikewheeleer]

nice work — thanks for this!