The github renderer materializes plain Text per display rebuild, so its
animatedPendingPreview opt-in requested 30fps repaints with a frozen
glyph for the whole run_watch wait; drop the flag. Custom tools with
only one of renderCall/renderResult never route to the animated generic
fallback, so gate the unregistered-renderer spinner on both being
absent. Regression tests for both no-tick contracts.
Added renderer metadata for pending and partial result paths that visibly consume spinner frames.
Stopped headerless bash pending previews from scheduling repaint ticks while preserving eval and shell header animation.
Excluded running async result snapshots from live partial spinner intervals so finalized background tool rows do not repaint scrollback.
Added regression coverage for async bash snapshots staying static.
Started live partial tool spinner intervals for non-static tool blocks and forwarded spinner frames through eval and shell-style renderers.
Added regression coverage for live eval and shell preview spinner frames.
Fixes#4170