v0.1.0-alpha.61

Chrome greys move off yellow to where Apple's own greys sit -- the blue
cast was corrected too far, and the text ranks had drifted to R-B +7.

Fixes a file explorer that opened at three quarters of the window and
could not be dragged back: the split view identified dividers by index,
so with the history panel hidden the explorer inherited the history
panel's limits. The history divider gains the terminal floor the
explorer's already had.

Adds create, rename and trash to the file explorer context menu, and
Codex agent status through its own hooks -- marker-scoped, backed up, and
refusing outright any config it cannot fully recognise.